Little circles of lamination popping off

[Dhyde]

1999 Winnebago Spirit motor home. We noticed this when we picked up the RV from winter storage (outside in Michigan). It is on the underside of the cabin, just over the cab. There are hundreds of tiny circles/dots that are popping off, leaving exposed underlayment. Our RV guy said he had only seen this once before and it was also on a Winnebago. It is the entire width of the motor home and about 12” wide.
Has anyone seen or had experience with this?
Someone suggested possibly that moisture/rain ran off the roof, down and around the front then under the cabin , or maybe a condensation type of scenario. Then those droplets froze in place and popped the lamination off in little dots.
Looking for ideas on how to deal with it.

[CJBROWN]

Are you sure that panel is fiberglass or plastic? That looks a lot like corrosion of an aluminum panel.

The solution is to replace the panel.

I could also be a telltale indication of a water leak, somewhere above that panel.

[twinboat]

Look up Blisters on boat hulls.

https://www.boatus.com/expert-advice...ops%20blisters.

[chunker]

It could be just the lighting of the picture but it looks like de-lamination bubble on the side panel below and forward of the side window. To me indicates a water leak and damages.