I'm doing Holiday related stuff too. Today I embroidered an AnitaGoodesigns pillow with a Santa. When I needed color # 22 I realized I switched #20 and #21....considering it's in an embroidery hoop it's hard to rip but I had to so out came my very shard scissors and carefully I snipped the threads. Of course I snipped a hole in the fabric!! Because of the dense embroidery I just used some WSS on top and embroidered the whole thing again. No shifting which is a miracle!
Now hopefully it will hold when it has to be washed. Which will be one day in the far future