I stopped wrapping DS at 9 weeks and switched him to sleeping bags. I didnt wrap him of a day, only at night and he went in the no problems. DD i am doing the same.. just am waiting for the stains to soak out of the sleeping bags atm then she'll be in them.
Perhaps you can try it just during the day? But yeh maybe he doesnt want to be wrapped anymore. I know alot of babies like to sleep with their arms above their heads.. being wrapped restricts that.