Is it by any chance where the locking peg/pin mechanism is located, in the centre at either end? Just wondered as we had a Fleurette Tamaris for years before moving to Eribas. That had water ingress when we bought it and had caused the veneer to bubble and lift.
It was caused by a missing flap of pvc on the outside of the end poptop section. It should cover the locking peg when the roof is up and prevent water tracking back into the caravan, a bit like a little cycle cape! In our experience, they are easily ripped off if the peg isn't pulled in when dropping the roof.