bubbles under paintwork - both sills??

[Twayblade]

Can anyone help with this? I am looking at buying a low mileage <40k 1991 M100 SE which is in V good nick given that its 30 yrs old. I have been told the car has been stored dry for the last 10 yrs and the MOT history shows it has only covered approx 8k miles in that time.
The bodywork condition is good apart from the outer sills which show a small amount of bubbling under the paintwork, one side is slightly worse than the other? Does anyone have any experience of this with the M100, or can anyone offer any insight or guidance on this ?
many thanks
Tway

[Blaster]

Depending on the size it could be that it was painted in a damp environment. GRP is notorious for having damp trapped under the paint work if it is porous and not dried completely before painting. Mine is showing some.