I'm in the process of putting a sweater together and discovered that the sleeve cap needs to be 2 inches bigger to fit the sides and back of a cardigan. The pattern has a set-in sleeve. I've already bound off the top of the cap. Do I just undo the bound-off part and unknit some rows and reknit the cap? I followed the pattern to decrease a stitch a row for a certain number of rows to the top of the cap, but it obviously ended up too short. Any help would be greatly appreciated.