When I do PPing I might glue the very 1st piece but only in an area that will be chopped off later, not to a section of the actual block. I glued to the actual block section and found it hard to remove so went to outside the seam allowance and it worked better. Had one block I was working on and it started in the middle of the section so had to use straight pins instead. Learned my lesson fast about when and where to use glue.