I noticed big time drain yesterday, but I had rejoined an old group, and it had a lot of chatterboxes, so there was constant notifications coming in. Leaving that group, plus the update, seems to have calmed down my battery drain.
The other thing I did was in Settings/General/Background App Refresh, turn off BBM. That definitely seems to have helped. Yesterday I was at the point of uninstalling, but doing the above seems to have settled things down.