This is a double roll on the B on the A string. Instead of playing B,A,B D,A,G, I play a double roll with the B on the A string. This variation I play in the second Bar of the first part.

This variation I play in the fourth Bar of the first part. Instead of playing DBB BAG I play EDB BAG.
The proceeding bar ends on the E and I use that same note to start the variation which I think accentuates the variation.