They probably fixed all the bugs they considered essential, and the rest is just nice to have fixes that can be moved to the next cycle if necessary (and they still have a week to work on them before release, although they might be careful not to introduce severe bugs now).

The general idea with this approach is that it doesn’t make sense to block a release on a few bugs worked on by only a subset of available developers and having the rest idle - the project can be finished faster by moving the remaining tasks over to the next release and accepting the bugs in the meantime.