This is an on-going problem due to the unnecessary duplication of data across release branches; it is also an issue with the generated changelog.html files for each branch. Rather than trying to patch over the problem again, we should fix it permanently by removing the duplication. One way that I believe would work is to change the whatsnew and changelog "templates" for each release branch to only contain the data for its branch and to include links at the bottom to the on-line version of the previous branch's whatsnew or changelog. There would also likely need to be some release manager actions added to PEP 101 and release scripts to delete the previous branch's whatsnew when creating a new release branch, i.e. at beta 1 time. One minor downside to this is that any off-line version of the docs would now have a link to the on-line whatsnew and changelog for previous releases rather than a fully self-contained off-line version but that's probably better than having incomplete and/or incorrect information as we do today. @python/python-release-managers