I have 11 sheets of WBP plywood and the edges have soaked up some water and started to bubble/delaminate. I purchased them for a roof deck, and am very concerned that going onto a roof they will get worse. Is it because the edges need sealing? I've had the sheets for about 3 weeks, I was under the impression that WBP would be able to absorb some water without bubbling. They haven't been submersed or anything.