It didn’t stick to the blue top film.
VC is a hybrid polyurethane and usually sticks to just about everything. I don’t know if a straight poly would work like Sikaflex 1a or even Fuze It.
I was using it to seal the “pinhole” at a dormer front and side to roof corners.
Called GAF and they said only to use roofing cement.
This is disappointing because sealants stick better than roofing cements.