I have one dormer on my house, it faces north. All the dormer siding and trim are new ,custom run ,made of KD heart poplar. Siding has ship lap with large bead flanked by large bevels. Installed with boards parallel to the 13/12 roof. Pieces were treated with copper naphthalate including the lower vertical cuts. CN dried for MONTHS before priming and painting on the ground. When the contractor installed the pieces with screws we put a 1/16thplus strip of wood over each stud. House wrap is under those spacers ,and covers all sheathing. He put the second coat of sand colored SW Emerald immediately after install. I was in and out of house as needed. Back outside ,he yelled down " besides putting second coat on all,I put another coat over the beads and screw". He's the painter but I was the only one who new not to apply paint over still wet paint. Now ,some months later the paint is peeling in that 3rd coat area only. SW telephone help said just take off top coat with alcohol and don't recoat. I'm thinking scrape and sand carefully and repaint affected area with one coat not heavily aplied. Would appreciate your guidance. The hardiplank and all other wood trim show no problems.