How bad is it billowing up? A small area or a large area that would probably require adhesive to get it back down? If it is a small bubble and you've found it caused by air getting in at the front cap,I would have no problem using EternaBond tape to solve it. Once that stuff is on, it is very difficult to remove. I had a leak around a living room vent in SOB and could never really figure out where the water was getting in so I sealed the entire vent with eternabond and never had a problem after that. When a small leak developed in the bedroom closet I did the same thing across the entire front where the cap and roof material meet and the leak never came back. I believe in that stuff so much that I've been thinking about doing it to the front and rear caps of the Redwood just for preventative measures. After all, that's how most manufacturers seal the slide out roofs. You have to use a heat gun to remove that stuff so I would want to make sure the loose material is adhered before I put the eternabond down. You can go to the Alpha products website or call them and they can tell you what adhesive to use on the Alpha Ply roof.
Rick and Mindy
2013 Redwood 31SL, 2011 Ford F350 SRW, 6.7, Crew Cab with Firestone Bags, Titan Disc Brakes