Rust or Not?

Those bubbles indicate my above post.
There must be thin metal from rust behind surface creating pin holes that were covered up or
surface rust ground down initially leaving half the thickness of sheetmetal with rust behind it eventually
overtime moisture from behind breaks thru metal pushing out plastic initial repair.(bubbles)
That area needs to be cut out going inches if not more beyond bubbles and new sheetmetal welded in properly.
Hopefully its just those relatively small areas and not complete wheel well area....

Dave