Ubuntu Aims For Higher Quality LTS Point Releases
New restrictions will be in place beginning with Ubuntu 20.04.3 LTS this summer to try to enforce better quality releases with less regressions by enforcing better quality control.
The change beginning with Ubuntu 20.04.3 LTS will require that stable release update (SRU) procedures are followed even for release blockers. This will require that every fix follows the same verification, regression analysis, and aging period process. The tighter quality controls will likely lead to slips in release targets if bugs are found in the release candidates for new point releases, as it will first need to go through the verification and aging process.
Canonical's Lukasz Zemczak who is on the Ubuntu Foundations Team noted in the change, "Delaying a point-release is unfortunate, but better than lowering our quality standards. We had a few cases already where our last minute fixes, fast-tracked under time pressure, were not tested thoroughly enough and introduced regressions (or, similarly annoying, appeared to be only partial fixes). As quality is the most important aspect of any Ubuntu release, we want to make sure users get the best experience of our point-release images."
As for the impact on Ubuntu developers/packagers, "Please be sure to land any critical or important changes for the given point-release as soon as possible, preferably with release -2 weeks as the deadline. Every other last minute SRU will potentially be risking the delay of the release. Also, once -proposed is disabled for dailies, it would also be wonderful if the pre-point-release images could get as much testing as possible. The sooner critical issues are identified, the higher chances are we will not have to slip the release. I'm pretty confident that with these changes we will all benefit equally."
More details within this mailing list post announcing the change to improve the point release quality/process.