I've also been having problems with my bluetooth since the last update. My devices won't even pair. It is extremely annoying. My phone is up-to-date I think. Is Samsung doing anything to fix this?
I downloaded the new update last night but saw no difference in fitbit connectivity, still got the message unable to pair and even in the fitbit app it would tell me device not found. I also updated the fitbit app. I figured I would just have to continue syncing my fitbit data with my iPad. Then this morning I heard the email notification from my phone and it immediately came through on my fitbit! When I checked the app all my data for the day had already been synced, however when I tried to phone myself I didn't get a call notification on my fitbit, but at least it's some progress?!
People seem to hate the new Fitbit update. But as I said, since I updated my A8 last week it's been great. You might not have the newest. If it is the old software no one can fix it.