I will not comment on the Lemon Law as I have no experience in this area. However, I had 2 vehicles with intermittent problems. One was a Eurovan that sometimes refused to start (dead). It took a long time to trace the problem to a cracked fuse block that was replaced under warranty even if the vehicle was past its warranty period. The other was a Subaru Outback with the erratic "Check Engine" light. It was at the dealer so many times (up to twice a day!) The dealer really tried to fix the problem (replaced various sensors, redid some connections, etc.) without success until they had to bite the bullet and replace the complete wiring harness (an expensive job they were trying to avoid). No more problems after that. Again the repair was done under warranty even if it was past the limit date.
In both cases, I had kept records to demonstrate the same problem existed from the early days of the vehicle. My suggestion is to keep asking politely the dealer to fix the problem and keep records of all the facts. I might take a while to fix the problem and be cheaper that suing in the long run.
I hope for you they quickly find the gremlin so you can enjoy your B.
Alain