Many packages have pre/post install/remove scripts. These scripts are not regularly being tested in an on-target upgrade environment. A test should be created uses the appropriate package feed mechanism, and on-target package manager to update from one build to the next. Further the milestone testing should include a test that installs the previous milestone, and then attempts to update to the next milestone. The final -RC- testing should also validate that updates from the previous Yocto Project version to the new one work, and produce a valid system.
We should be testing the intermediate Milestones RCs are able to update from the prior release, not just the final RC.
This is a duplicate of bug 4304. *** This bug has been marked as a duplicate of bug 4304 ***
verified as per above comments.