In Core, there are two major releases (May and November) and two minor releases (February and August) each year. Major and minor releases are release versioning types given to categorize the stages throughout the development process. As you can see the table below, there are slight differences between them. Patches and hotfixes are another type of release, but these do not require partners to migration. So we won't focus too much on those here.
|Requires testing by partners
|Reconstruction and Improvements
Optional * - Partners have the option to migrate
Differences and similarities between major and minor releases.
It is recommended for both major and minor releases start migrating 8 weeks before the release which is when Core reaches code freeze. And the migration process should be completed 2 weeks after the code freeze. Then the testing should be done on the RC (Release Candidate) which should be available 4 weeks before the release. And the testing should be completed at least 2 weeks before the release.
Recommended migration timeline from code freeze until the release for both major and minor releases.
It is also recommended to go through a migration test and smoke test once the migration has been performed. The full regression is done only after the smoke test to smooth out the testing process. Although migration is optional for a minor release, it is still recommended to go through the test. Therefore, smoke tests are highly recommended to be done for both major and minor releases.