So he's in a 4 x 1 cage? That's on the small side if he's 6 ft. My guess would be that he's wanting some more space. The way I go with cage sizes for all snakes is either one square foot of cage per foot of cage, or that the sum of the front of the cage and one side should equal at least the length of the snake. Otherwise all your husbandry sounds perfect to me.
Also just on a side note, how are you measuring the temps? And you might want to consider putting an identical hide on the other side of the enclosure, from what the pics show he only has one hide.