The first batch of flander's I made didn't turn out nearly sour enough for my tastes. I fermented with 1056 and added the Roselare bugs in the secondary and inserted a rubber stopper with an oak dowel in it. The second batch I made I pitched directly on the bugs and added a pack of US05, let it ferment out and tranferred when the pellicle fell after 1 year. That beer took 2nd at the NHC this year.
I've heard from other brewers that the 1st generation of Roselaere isn't sour enough, the 2nd generation is just right and 3rd generation is too sour. YMMV.
So wait, you pitched round 2 on top of the bugs left from round 1 (year old)?
Also, do you rack after primary or do you complete all fermentation and aging in one carboy?