perched above my plateau...again

I've been maintaining for 2 years now, and for the umpteenth time I'm above my plateaued final level by 4-5 lbs.  A birthday party, a couple of restaurant meals and here we go again....

This is not a real weight gain.  I've found that I can shock myself off of the perchand drop the 4-5 lbs  with a couple days of 500+ calorie deficits.  But if I don't do this I sit there stagnant.  I notice the gain as swollen fingers and leg muscles. 

Anyone else have a similar experience?