Missing sidebar after 2.1 update

I recently updated to 2.1 and my right sidebar disappeared from all pages. When I reverted to 2.0 it came back. However, I then just uploaded the changed files (from this post – http://blueowlcreative.com/support_wp/forums/topic/is-there-changelog-for-may-2014-update/) and the update worked and the sidebar stayed. Which would seem to imply that some other file changes made the sidebar disappear. Are you sure no other files were changed in the 2.1 update?

It seems fine now and no-one else seems to have posted with the same problem, so it may well just be my particular setup. But I thought I’d ask the question…