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ACS produces PreReleases and Releases aligned with ALMA delivery life cycle. This means that every 2 months a new release is scheduled for ALMA with name COMMON-<YYYY><MMM> (COMMON-2019JUN, COMMON-2019AUG, etc.), the development of a specific release starts around 2 months before the release. The "Requirements Deadline" is reached around 1 month before the end of development and after this last month ends, the "Pull Requests for Verification" should have been created. At this point the verification phase starts which lasts roughly 18 days (3 working weeks). In the case of COMMON, there's no validation phase, although some tickets may require validation, which should be carried out along an ONLINE-<YYYY><MMM> release validation phase. During this life-cycle, pre-releases and releases are created.

The dates for each of these phases is coordinated by the Release Manager and the information is persisted in Release Planning confluence page.

Pre-Release

ACS Pre-releases are intermediate roll-outs of the COMMON software, which are used by other developers to anticipate changes and to prepare their environments for development of their upcoming releases. In principle, it would be possible to have 1 ACS pre-release at the end of the development phase, along with preparing all the "Pull Requests for Verification". Usually, at least one additional ACS pre-release is prepared before, so developers can anticipate their work and have configured their building and testing environments beforehand. There are situations that also trigger additional ACS pre-releases, like finding important bugs during verification or development time.

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