On re-do puzzles, autofill has never worked for me, so I have to go back and put all the letters in one at a time. On the last day of the June competition, I noticed I had lost my 100%, and there was a game that had registered, but never came up. I went back and solved it. It was already 40 minutes old, but it preserved 100%. It threw me from 16th to 17th on the time competiton.