If anybody is following me, I had my car flashed after the 10,000km service (12B37) with bad results (jerkiness, sluggish feel, shift hesitation).
Took it to another dealer (to fix a steering gear problem) and they suggested to reflash the transmission (12B37) again. They followed the re-learning pattern and my car is shifting perfectly. Just a heads up for anyone having problems with this new update, make sure that your dealer takes the time to go through the re-learning procedure. I am guessing the other dealer didn't go through it.