Rollback to stable doesn't work after a while

As far as roll back is concerned, I think that's the intended behaviour and it makes sense to me. When you update, the old version is stored as "previous", regardless of the branch. If you want to roll back, you roll back to the version you were using before you updated. Anything else wouldn't really make sense, would it? However, you ought to be able to select the stable branch and update to that, but as of -beta30 that wasn't working - the Branch option switches back to next, which is a bug and has been acknowledged in another thread. It's possible it's fixed in -beta35 - I haven't read that thread yet.

Yes exactly this.   Thanks.