I mistakenly filled my pool before pulling the winter cover off. When I pulled the cover off I found the liner had pulled away from the coping over a good 18" stretch. I expect I have to drain the pool, pour hot water on the liner, and try to work it back. Boiling hot water by itself doesn't give me nearly enough stretch, so I will have to drain. I'm concerned by the space behind the liner, however. I will have to stretch it about 2 inches and, at the very top, there will be about a half inch between the wall and the liner once I fix it. (See pictures.) That seems like it could pull right out again. Is the polymer wall shifting? Or am I paranoid? (Or both?) Thanks for any advice!