I have a 2014 hunter 33.5 that is out of warranty. It is used in a fractional share program by people other than me. Members are responsible for damage they do to the boat. Last weekend I had the pleasure of using my own boat and when washing her down found a hole and spider cracks surrounding it in the wall of cockpit near floor that weren't there the last time I used the boat. The fractional program manager told me that I am responsible for repair because air voids are very common in Hunters and that a member couldn't have caused it. My question is what causes an air void to suddenly show itself? Does regular wear and tear overtime cause them to show or is it more usually caused to show by an impact? Photo attached. Thanks.

