Then, post nap, things got a little ugly. He tried for quite a while but nothing came out.
About half an hour later, we had some lapses. In about 10 minutes we had a major pee accident, then a super colossal poop accident. He announced the pee, but when I could see the giant load in his underwear he denied it.
The final potty trip of the day was unlike all the others earlier in the day. He sat down and immediately peed. It was a thing of beauty and left us optimistic for tomorrow.