- Retiring a preview channel now requires the stable head to carry every
package the preview ships. An Intel preview could otherwise be pinned to an
arm64-only stable head it has no package in, and its client would fail to
resolve the retirement for good.
- The docs and release.py's next-steps text said Intel Macs stay on the last
Intel release's feed. They do not: promote rewrites the one shared macOS
stable feed with the arm64 leg, so Intel Macs get no update until a release
opts Intel back in. Only the Termux APT channel stays on its previous release.
- New scripts/releases/optional_platforms.py holds the claim flag, jobs,
handoff, target and smoke of each opt-in platform; stable.py, channel
releases, release artifacts and the entrypoint read from it. stable.py is
back under 1,000 lines. No behavior change.
- Test: a macOS Intel receipt against a baseline without Intel plans no
upgrade arm (baseline=none); against a baseline with Intel it plans one.
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