Yeah ... 3,500 extra cals = 1 extra lb on you! If its over a week that's only an extra 500 cals a day ... What's that? A couple of large glasses of wine? A cheese sandwich? A large slice of cheesecake? It wouldn't take much. That's why we have to be ever vigilant!
Personally I've found maintaining hasn't been/isn't so much a matter of staying the same as gaining a few lbs and then losing them again. Once or twice it's been more than a few lbs - quite a lot more in fact

. It's always best to try not to let it get out of hand but sometimes it's like you just can't control it. You do come to understand though, that each phase will pass. So make the most of when you're strong and try to ride out the tougher times without doing tooooo much damage.
I sincerely hope you will be one of the luckier ones who finds their way quickly and effectively, but whatever happens you've come a long way and there no need to go back to where you were ever again!
I've tried various ways to maintain. At the moment (well not this VERY moment because I'm away for the weekend but 'at the moment' in general

) I'm trying the JUDDD diet (if you don't know what it is there's a forum about it on this site). I still have a few lbs I'd like to re-lose

and I dare say that'll be a few more by the time we're back from this weekend

.... It's such a difficult time of year though! But there's never a good time is there?!
Look forward to seeing how you get on

x