diff --git a/news/13950.feature.rst b/news/13950.feature.rst
new file mode 100644
index 0000000000..0076860930
--- /dev/null
+++ b/news/13950.feature.rst
@@ -0,0 +1 @@
+Honor ``--only-final`` when sourcing requirements with ``-r pylock.toml``.
diff --git a/news/13963.feature.rst b/news/13963.feature.rst
new file mode 100644
index 0000000000..e91dfc4f75
--- /dev/null
+++ b/news/13963.feature.rst
@@ -0,0 +1 @@
+Better error messages in case of conflicts with requirements from ``-r pylock.toml``.
diff --git a/news/14168.feature.rst b/news/14168.feature.rst
new file mode 100644
index 0000000000..28ac0b64b7
--- /dev/null
+++ b/news/14168.feature.rst
@@ -0,0 +1 @@
+Add support for ``pylock.toml`` ``upload-time`` field, so ``--uploaded-prior-to`` works with ``-r pylock.toml``.
diff --git a/src/pip/_internal/cli/req_command.py b/src/pip/_internal/cli/req_command.py
index f09267f35b..f58a970613 100644
--- a/src/pip/_internal/cli/req_command.py
+++ b/src/pip/_internal/cli/req_command.py
@@ -370,15 +370,15 @@ def get_requirements(
                 for package, package_dist in select_from_pylock_path_or_url(
                     filename, session=session
                 ):
-                    requirements.append(
-                        install_req_from_pylock_package(
-                            package,
-                            package_dist,
-                            filename,
-                            options.format_control,
-                            user_supplied=True,
-                        )
+                    req_to_add, locked_link = install_req_from_pylock_package(
+                        package,
+                        package_dist,
+                        filename,
+                        user_supplied=True,
                     )
+                    requirements.append(req_to_add)
+                    if locked_link:
+                        finder.add_locked_link(package.name, locked_link)
                 continue
             for parsed_req in parse_requirements(
                 filename, finder=finder, options=options, session=session
diff --git a/src/pip/_internal/index/package_finder.py b/src/pip/_internal/index/package_finder.py
index df786a62b5..cf4a2eeb65 100644
--- a/src/pip/_internal/index/package_finder.py
+++ b/src/pip/_internal/index/package_finder.py
@@ -662,6 +662,9 @@ def __init__(
             BestCandidateResult,
         ] = {}
 
+        # projects for which a link is locked from a pylock
+        self._locked_links: dict[NormalizedName, Link] = {}
+
     # Don't include an allow_yanked default value to make sure each call
     # site considers whether yanked releases are allowed. This also causes
     # that decision to be made explicit in the calling code, which helps
@@ -876,7 +879,8 @@ def process_project_url(
     def find_all_candidates(self, project_name: str) -> list[InstallationCandidate]:
         """Find all available InstallationCandidate for project_name
 
-        This checks index_urls and find_links.
+        This checks index_urls and find_links, unless a locked link is known
+        for that project.
         All versions found are returned as an InstallationCandidate list.
 
         See LinkEvaluator.evaluate_link() for details on which files
@@ -887,6 +891,23 @@ def find_all_candidates(self, project_name: str) -> list[InstallationCandidate]:
 
         link_evaluator = self.make_link_evaluator(project_name)
 
+        if locked_link := self._locked_links.get(canonicalize_name(project_name)):
+            # If a locked link is known for that project, do not check
+            # index_urls nor find_links. We don't use get_install_candidate here,
+            # because if a locked link is unsupported (due to format control,
+            # release control or otherwise), we want to error out immediately
+            # instead of ignoring it.
+            result, detail = link_evaluator.evaluate_link(locked_link)
+            if result != LinkType.candidate:
+                raise InstallationError(
+                    f"Could not install locked package {project_name!r} "
+                    f"from {locked_link.comes_from!r}: {detail}"
+                )
+            self._all_candidates[project_name] = [
+                InstallationCandidate(project_name, detail, locked_link, locked=True)
+            ]
+            return self._all_candidates[project_name]
+
         collected_sources = self._link_collector.collect_sources(
             project_name=project_name,
             candidates_from_page=functools.partial(
@@ -1076,6 +1097,16 @@ def _should_install_candidate(
         )
         raise BestVersionAlreadyInstalled
 
+    def add_locked_link(self, project_name: NormalizedName, locked_link: Link) -> None:
+        assert not self._all_candidates
+        if project_name in self._locked_links:
+            raise InstallationError(
+                f"Multiple locked links provided for {project_name}: "
+                f"{self._locked_links[project_name]} and {locked_link}"
+            )
+
+        self._locked_links[project_name] = locked_link
+
 
 def _find_name_version_sep(fragment: str, canonical_name: str) -> int:
     """Find the separator's index based on the package's canonical name.
diff --git a/src/pip/_internal/models/candidate.py b/src/pip/_internal/models/candidate.py
index 88ecc99258..0639466c4c 100644
--- a/src/pip/_internal/models/candidate.py
+++ b/src/pip/_internal/models/candidate.py
@@ -13,11 +13,15 @@ class InstallationCandidate:
     name: str
     version: Version
     link: Link
+    locked: bool
 
-    def __init__(self, name: str, version: str, link: Link) -> None:
+    def __init__(
+        self, name: str, version: str, link: Link, locked: bool = False
+    ) -> None:
         object.__setattr__(self, "name", name)
         object.__setattr__(self, "version", parse_version(version))
         object.__setattr__(self, "link", link)
+        object.__setattr__(self, "locked", locked)
 
     def __str__(self) -> str:
         return f"{self.name!r} candidate (version {self.version} at {self.link})"
diff --git a/src/pip/_internal/req/constructors.py b/src/pip/_internal/req/constructors.py
index 6dcac66737..49158942b7 100644
--- a/src/pip/_internal/req/constructors.py
+++ b/src/pip/_internal/req/constructors.py
@@ -23,7 +23,6 @@
 from pip._vendor.packaging.utils import parse_sdist_filename, parse_wheel_filename
 
 from pip._internal.exceptions import InstallationError
-from pip._internal.models.format_control import FormatControl
 from pip._internal.models.index import PyPI, TestPyPI
 from pip._internal.models.link import Link
 from pip._internal.models.wheel import Wheel
@@ -585,65 +584,57 @@ def install_req_from_pylock_package(
         | pylock.PackageWheel
     ),
     pylock_path_or_url: str,
-    format_control: FormatControl,
     user_supplied: bool,
-) -> InstallRequirement:
-    pass
+) -> tuple[InstallRequirement, Link | None]:
+    """Construct an InstallRequirement from a pylock package and artifact.
+
+    If the artifact is a Sdist or Wheel, also return a locked Link which
+    is meant to override candidates from indexes or --find-links.
+    """
     # TODO: validate file size
     if isinstance(package_dist, pylock.PackageVcs):
-        return InstallRequirement(
-            req=Requirement(
-                f"{package.name} @ "
-                f"{package_vcs_requirement_url(pylock_path_or_url, package_dist)}"
+        req_url = package_vcs_requirement_url(pylock_path_or_url, package_dist)
+        return (
+            InstallRequirement(
+                req=Requirement(f"{package.name} @ {req_url}"),
+                comes_from=pylock_path_or_url,
+                user_supplied=user_supplied,
             ),
-            comes_from=pylock_path_or_url,
-            user_supplied=user_supplied,
+            None,
         )
     elif isinstance(package_dist, pylock.PackageArchive):
-        return InstallRequirement(
-            req=Requirement(
-                f"{package.name} @ "
-                f"{package_archive_requirement_url(pylock_path_or_url, package_dist)}"
+        req_url = package_archive_requirement_url(pylock_path_or_url, package_dist)
+        return (
+            InstallRequirement(
+                req=Requirement(f"{package.name} @ {req_url}"),
+                comes_from=pylock_path_or_url,
+                hash_options=_pylock_hashes_to_hash_options(package_dist.hashes),
+                user_supplied=user_supplied,
             ),
-            comes_from=pylock_path_or_url,
-            hash_options=_pylock_hashes_to_hash_options(package_dist.hashes),
-            user_supplied=user_supplied,
+            None,
         )
     elif isinstance(package_dist, pylock.PackageDirectory):
-        req = package_directory_requirement_url(pylock_path_or_url, package_dist)
+        req_url = package_directory_requirement_url(pylock_path_or_url, package_dist)
         if package_dist.editable:
-            return install_req_from_editable(
-                req,
-                comes_from=pylock_path_or_url,
-                user_supplied=user_supplied,
+            return (
+                install_req_from_editable(
+                    req_url,
+                    comes_from=pylock_path_or_url,
+                    user_supplied=user_supplied,
+                ),
+                None,
             )
         else:
-            return install_req_from_line(
-                req,
-                comes_from=pylock_path_or_url,
-                user_supplied=user_supplied,
+            return (
+                install_req_from_line(
+                    req_url,
+                    comes_from=pylock_path_or_url,
+                    user_supplied=user_supplied,
+                ),
+                None,
             )
     else:
         # wheel or sdist
-        allowed_formats = format_control.get_allowed_formats(package.name)
-        if (
-            isinstance(package_dist, pylock.PackageSdist)
-            and "source" not in allowed_formats
-        ):
-            raise InstallationError(
-                f"source distributions are not permitted for package {package.name!r} "
-                f"and there is no compatible wheel for it in {pylock_path_or_url!r}"
-            )
-        if (
-            isinstance(package_dist, pylock.PackageWheel)
-            and "binary" not in allowed_formats
-        ):
-            if not package.sdist:
-                raise InstallationError(
-                    f"binaries are not permitted for package {package.name!r} and "
-                    f"there is no source distribution for it in {pylock_path_or_url!r}"
-                )
-            package_dist = package.sdist
         version = package.version
         if isinstance(package_dist, pylock.PackageWheel):
             if not version:
@@ -660,9 +651,12 @@ def install_req_from_pylock_package(
         ireq = InstallRequirement(
             req=Requirement(f"{package.name}=={version}"),
             comes_from=pylock_path_or_url,
-            locked_link=Link(requirement_url),
-            locked_version=version,
             hash_options=_pylock_hashes_to_hash_options(package_dist.hashes),
             user_supplied=user_supplied,
         )
-        return ireq
+        locked_link = Link(
+            requirement_url,
+            comes_from=pylock_path_or_url,
+            upload_time=package_dist.upload_time,
+        )
+        return ireq, locked_link
diff --git a/src/pip/_internal/req/req_install.py b/src/pip/_internal/req/req_install.py
index 7191f03a1a..f20707f3d2 100644
--- a/src/pip/_internal/req/req_install.py
+++ b/src/pip/_internal/req/req_install.py
@@ -79,8 +79,6 @@ def __init__(
         constraint: bool = False,
         extras: Collection[str] = (),
         user_supplied: bool = False,
-        locked_link: Link | None = None,
-        locked_version: Version | None = None,
     ) -> None:
         assert req is None or isinstance(req, Requirement), req
         self.req = req
@@ -106,14 +104,6 @@ def __init__(
             link = Link(req.url)
         self.link = self.original_link = link
 
-        # locked_link is the link from the lock file that must be used.
-        # A locked link InstallRequirement behaves similarly as a regular requirement
-        # that would be searched in indexes, except its artifact URL is known
-        # in advance. Notably, and contrarily to direct URL requirements and direct URL
-        # constraints, they do not cause the recording of direct_url.json.
-        self.locked_link = locked_link
-        self.locked_version = locked_version
-
         # When this InstallRequirement is a wheel obtained from the cache of locally
         # built wheels, this is the source link corresponding to the cache entry, which
         # was used to download and build the cached wheel.
diff --git a/src/pip/_internal/resolution/resolvelib/factory.py b/src/pip/_internal/resolution/resolvelib/factory.py
index ff1dab54c3..c9fb839d4a 100644
--- a/src/pip/_internal/resolution/resolvelib/factory.py
+++ b/src/pip/_internal/resolution/resolvelib/factory.py
@@ -32,7 +32,6 @@
 )
 from pip._internal.index.package_finder import PackageFinder
 from pip._internal.metadata import BaseDistribution, get_default_environment
-from pip._internal.models.candidate import InstallationCandidate
 from pip._internal.models.link import Link
 from pip._internal.models.wheel import Wheel
 from pip._internal.operations.prepare import RequirementPreparer
@@ -243,31 +242,6 @@ def _make_base_candidate_from_link(
                     return None
             return self._link_candidate_cache[link]
 
-    def _get_locked_installation_candidate(
-        self, ireqs: Sequence[InstallRequirement], name: str, specifier: SpecifierSet
-    ) -> InstallationCandidate | None:
-        locked_ireqs = [ireq for ireq in ireqs if ireq.locked_link]
-        if not locked_ireqs:
-            return None
-        if len(locked_ireqs) > 1:
-            raise InstallationError(
-                f"Multiple locks provided for package {name!r} in "
-                f"{', '.join(str(lir.comes_from) for lir in locked_ireqs)}"
-            )
-        locked_ireq = locked_ireqs[0]
-        assert locked_ireq.locked_link
-        assert locked_ireq.locked_version
-        if not specifier.contains(locked_ireq.locked_version):
-            raise InstallationError(
-                f"Locked version {locked_ireq.locked_version!s} "
-                f"for package {name!r} from {locked_ireq.comes_from!r} "
-                f"is not compatible with other requirements "
-                f"for the same package ({specifier!s})"
-            )
-        return InstallationCandidate(
-            name, str(locked_ireq.locked_version), locked_ireq.locked_link
-        )
-
     def _iter_found_candidates(
         self,
         ireqs: Sequence[InstallRequirement],
@@ -335,20 +309,12 @@ def _get_installed_candidate() -> Candidate | None:
             return candidate
 
         def iter_index_candidate_infos() -> Iterator[IndexCandidateInfo]:
-            if locked_ican := self._get_locked_installation_candidate(
-                ireqs, name, specifier
-            ):
-                # Locked InstallRequirements must behave as if they would have
-                # been found on an index, except the link is already known, so we don't
-                # ask the finder for the best candidate in that case.
-                icans = [locked_ican]
-            else:
-                result = self._finder.find_best_candidate(
-                    project_name=name,
-                    specifier=specifier,
-                    hashes=hashes,
-                )
-                icans = result.applicable_candidates
+            result = self._finder.find_best_candidate(
+                project_name=name,
+                specifier=specifier,
+                hashes=hashes,
+            )
+            icans = result.applicable_candidates
 
             # PEP 592: Yanked releases are ignored unless the specifier
             # explicitly pins a version (via '==' or '===') that can be
@@ -757,6 +723,7 @@ def _report_single_requirement_conflict(
 
         # Check if only final releases are allowed for this package
         version_type = "version"
+        allows_pre = None
         if self._finder.release_control is not None:
             allows_pre = self._finder.release_control.allows_prereleases(
                 canonicalize_name(req.project_name)
@@ -764,12 +731,32 @@ def _report_single_requirement_conflict(
             if allows_pre is False:
                 version_type = "final version"
 
-        logger.critical(
-            "Could not find a %s that satisfies the requirement %s (from versions: %s)",
-            version_type,
-            req_disp,
-            ", ".join(versions) or "none",
-        )
+        if len(cands) == 1 and cands[0].locked:
+            # The package finder ensures that requirements from pylock files
+            # have exactly one candidate. So we can provide a specific error
+            # message in this case.
+            if cands[0].version.is_prerelease and allows_pre is False:
+                logger.critical(
+                    "A pre-release version %s is specified in a provided lock file "
+                    "for %s but only final versions are allowed",
+                    cands[0].version,
+                    cands[0].name,
+                )
+            else:
+                logger.critical(
+                    "The requirement %s is not compatible with "
+                    "version %s specified in a provided lock file",
+                    req_disp,
+                    ", ".join(versions),
+                )
+        else:
+            logger.critical(
+                "Could not find a %s that satisfies the requirement %s "
+                "(from versions: %s)",
+                version_type,
+                req_disp,
+                ", ".join(versions) or "none",
+            )
         if str(req) == "requirements.txt":
             logger.info(
                 "HINT: You are attempting to install a package literally "
diff --git a/src/pip/_internal/utils/pylock.py b/src/pip/_internal/utils/pylock.py
index cd6c455e05..70df98693b 100644
--- a/src/pip/_internal/utils/pylock.py
+++ b/src/pip/_internal/utils/pylock.py
@@ -290,6 +290,8 @@ def select_from_pylock_path_or_url(
         ) from exc
 
     try:
+        # TODO: for completeness, pylock.select should support preferring sdist
+        # over wheels to support --no-binary
         yield from lock.select()
     except Exception as exc:
         raise InstallationError(
diff --git a/tests/data/lockfiles/pylock.certifi-with-upload_time.toml b/tests/data/lockfiles/pylock.certifi-with-upload_time.toml
new file mode 100644
index 0000000000..eba72c83d9
--- /dev/null
+++ b/tests/data/lockfiles/pylock.certifi-with-upload_time.toml
@@ -0,0 +1,8 @@
+lock-version = "1.0"
+created-by = "uv"
+
+[[packages]]
+name = "certifi"
+version = "2026.6.17"
+sdist = { url = "https://files.pythonhosted.org/packages/c9/c7/424b75da314c1045981bd9777432fad05a9e0c69daa4ed7e308bbaffe405/certifi-2026.6.17.tar.gz", upload-time = 2026-06-17T10:31:07Z, size = 134594, hashes = { sha256 = "024c88eeec92ca068db80f02b8b07c9cef7b9fe261d1d535abfd5abd6f6af432" } }
+wheels = [{ url = "https://files.pythonhosted.org/packages/ef/2f/c5464532e965badff2f4c4c1a3a83f5697f0d7c407ed0cda44aaa99bb451/certifi-2026.6.17-py3-none-any.whl", upload-time = 2026-06-17T10:31:06Z, size = 133289, hashes = { sha256 = "2227dcbaafe0d2f59279d1762ddddc37783ed4354594f194ffc31d20f41fc3db" } }]
diff --git a/tests/data/lockfiles/pylock.certifi-without-upload_time.toml b/tests/data/lockfiles/pylock.certifi-without-upload_time.toml
new file mode 100644
index 0000000000..f19c35c88f
--- /dev/null
+++ b/tests/data/lockfiles/pylock.certifi-without-upload_time.toml
@@ -0,0 +1,8 @@
+lock-version = "1.0"
+created-by = "uv"
+
+[[packages]]
+name = "certifi"
+version = "2026.6.17"
+sdist = { url = "https://files.pythonhosted.org/packages/c9/c7/424b75da314c1045981bd9777432fad05a9e0c69daa4ed7e308bbaffe405/certifi-2026.6.17.tar.gz", size = 134594, hashes = { sha256 = "024c88eeec92ca068db80f02b8b07c9cef7b9fe261d1d535abfd5abd6f6af432" } }
+wheels = [{ url = "https://files.pythonhosted.org/packages/ef/2f/c5464532e965badff2f4c4c1a3a83f5697f0d7c407ed0cda44aaa99bb451/certifi-2026.6.17-py3-none-any.whl", size = 133289, hashes = { sha256 = "2227dcbaafe0d2f59279d1762ddddc37783ed4354594f194ffc31d20f41fc3db" } }]
diff --git a/tests/data/lockfiles/pylock.prerelease-archive.toml b/tests/data/lockfiles/pylock.prerelease-archive.toml
new file mode 100644
index 0000000000..fa11f5cffd
--- /dev/null
+++ b/tests/data/lockfiles/pylock.prerelease-archive.toml
@@ -0,0 +1,11 @@
+lock-version = "1.0"
+created-by = "pip"
+
+[[packages]]
+name = "pkg-prerelease"
+
+[packages.archive]
+path = "../packages/pkg_prerelease-1.0a1-py3-none-any.whl"
+
+[packages.archive.hashes]
+sha256 = "5b170526e52d17d1b2e0162c006142e792293a7975a1f51df39035f1b14768d5"
diff --git a/tests/data/lockfiles/pylock.prerelease-wheel.toml b/tests/data/lockfiles/pylock.prerelease-wheel.toml
new file mode 100644
index 0000000000..d048720bce
--- /dev/null
+++ b/tests/data/lockfiles/pylock.prerelease-wheel.toml
@@ -0,0 +1,13 @@
+lock-version = "1.0"
+created-by = "pip"
+
+[[packages]]
+name = "pkg-prerelease"
+version = "1.0a1"
+
+[[packages.wheels]]
+name = "pkg_prerelease-1.0a1-py3-none-any.whl"
+path = "../packages/pkg_prerelease-1.0a1-py3-none-any.whl"
+
+[packages.wheels.hashes]
+sha256 = "5b170526e52d17d1b2e0162c006142e792293a7975a1f51df39035f1b14768d5"
diff --git a/tests/data/packages/pkg_prerelease-1.0a1-py3-none-any.whl b/tests/data/packages/pkg_prerelease-1.0a1-py3-none-any.whl
new file mode 100644
index 0000000000..424f2d7a4f
Binary files /dev/null and b/tests/data/packages/pkg_prerelease-1.0a1-py3-none-any.whl differ
diff --git a/tests/functional/test_install_pylock_reqs.py b/tests/functional/test_install_pylock_reqs.py
index 20ec058546..1f94754cd5 100644
--- a/tests/functional/test_install_pylock_reqs.py
+++ b/tests/functional/test_install_pylock_reqs.py
@@ -222,10 +222,8 @@ def test_install_pylock_no_binary(
         "--no-binary=simplewheel",
         expect_error=True,
     )
-    assert (
-        "binaries are not permitted for package 'simplewheel' and "
-        "there is no source distribution for it in" in result.stderr
-    )
+    assert "Could not install locked package 'simplewheel'" in result.stderr
+    assert "No binaries permitted for simplewheel" in result.stderr
 
 
 def test_install_pylock_only_binary(
@@ -242,10 +240,8 @@ def test_install_pylock_only_binary(
         "--only-binary=:all:",
         expect_error=True,
     )
-    assert (
-        "source distributions are not permitted for package 'simple' and "
-        "there is no compatible wheel for it in" in result.stderr
-    )
+    assert "Could not install locked package 'simple'" in result.stderr
+    assert "No sources permitted for simple" in result.stderr
 
 
 def test_install_pylock_only_binary_ignored_for_archives(
@@ -267,3 +263,121 @@ def test_install_pylock_only_binary_ignored_for_archives(
     )
     assert "experimental" in result.stderr
     assert "Would install simple2-3.0" in result.stdout
+
+
+def test_install_pylock_default_prerelease(
+    script: PipTestEnvironment,
+    shared_data: TestData,
+) -> None:
+    """Prereleases are allowed by default."""
+    pylock_path = shared_data.lockfiles.joinpath("pylock.prerelease-wheel.toml")
+    result = script.pip(
+        "install",
+        "--no-index",
+        "--dry-run",
+        "-r",
+        pylock_path,
+        allow_stderr_warning=True,
+    )
+    assert "experimental" in result.stderr
+    assert "Would install pkg-prerelease-1.0a1" in result.stdout
+
+
+def test_install_pylock_reject_prerelease(
+    script: PipTestEnvironment,
+    shared_data: TestData,
+) -> None:
+    """Prereleases are rejected when --only-final is set."""
+    pylock_path = shared_data.lockfiles.joinpath("pylock.prerelease-wheel.toml")
+    result = script.pip(
+        "install",
+        "--no-index",
+        "--dry-run",
+        "-r",
+        pylock_path,
+        "--only-final=pkg-prerelease",
+        expect_error=True,
+    )
+    assert (
+        "A pre-release version 1.0a1 is specified in a provided lock file "
+        "for pkg-prerelease but only final versions are allowed" in result.stderr
+    )
+
+
+def test_install_pylock_allow_archive_prerelease(
+    script: PipTestEnvironment,
+    shared_data: TestData,
+) -> None:
+    """--only-final does not influence direct URL requirements."""
+    pylock_path = shared_data.lockfiles.joinpath("pylock.prerelease-archive.toml")
+    result = script.pip(
+        "install",
+        "--no-index",
+        "--dry-run",
+        "-r",
+        pylock_path,
+        "--only-final=pkg-prerelease",
+        allow_stderr_warning=True,
+    )
+    assert "experimental" in result.stderr
+    assert "Would install pkg-prerelease-1.0a1" in result.stdout
+
+
+def test_install_pylock_conflict(
+    script: PipTestEnvironment,
+    data: TestData,
+) -> None:
+    pylock_path = data.lockfiles.joinpath("pylock.onewheel.toml")
+    result = script.pip(
+        "install",
+        "--no-index",
+        "--dry-run",
+        "-r",
+        pylock_path,
+        "simplewheel<2",  # conflict with simplewheel==2.0 in lock file
+        expect_error=True,
+    )
+    assert (
+        "The requirement simplewheel<2 is not compatible with version 2.0 specified "
+        "in a provided lock file" in result.stderr
+    )
+
+
+def test_install_pylock_uploaded_prior_to(
+    script: PipTestEnvironment,
+    data: TestData,
+) -> None:
+    pylock_path = data.lockfiles.joinpath("pylock.certifi-with-upload_time.toml")
+    result = script.pip(
+        "install",
+        "--no-index",
+        "--dry-run",
+        "-r",
+        pylock_path,
+        "--uploaded-prior-to=2026-01-01",
+        expect_error=True,
+    )
+    assert "Could not install locked package 'certifi' from " in result.stderr
+    assert (
+        "Upload time 2026-06-17 10:31:06+00:00 not prior to 2026-01-01" in result.stderr
+    )
+
+
+def test_install_pylock_uploaded_prior_to_missing_upload_time(
+    script: PipTestEnvironment,
+    data: TestData,
+) -> None:
+    pylock_path = data.lockfiles.joinpath("pylock.certifi-without-upload_time.toml")
+    result = script.pip(
+        "install",
+        "--no-index",
+        "--dry-run",
+        "-r",
+        pylock_path,
+        "--uploaded-prior-to=2026-01-01",
+        expect_error=True,
+    )
+    assert (
+        "pylock.certifi-without-upload_time.toml does not provide upload-time metadata"
+        in result.stderr
+    )