At PMPS+6, I heard Jenks meowing and found him in the kitchen trying to eat scant leftovers from the PMPS feeding. This was unexpected, and sometimes a sign of a low(er) reading. A quick check revealed a 58, a big change from the pink earlier in the day.
He clearly broke out of whatever was causing that high reading. So I fed him. Now I'll just have to stay up to make sure he doesn't do anything silly.