If it was doing it because of the ambient temp wouldn't it just go to the hot spot?
While I agree with the assessment that the ambient temps are a bit low it's not crazy low and I don't think it's the contributing factor.
6pm is the start of evening, that's when a ball python would be in hunting mode. What's your feeding schedule like? What size food are you using?
I also agree with you, hence why I mentioned hunting mode directly after that. Mine wanders around the cage pretty actively the night before feeding and the night of.
0.1 Red Axanthic P. regius | Mazikeen
0.1E. climacophora | Lan Fan