It's turning toward spring with longer daylight hours, so I doubt it's seasonal. This is when most snakes who were doing a winter fast start to break out of it (unless you're on the other side of the equator, in which case you're heading into fall and that could be possible). If it's a female at around 1000 grams, and there has been no other change in her environment or feed that you can account for, you may be looking at the Thousand Gram Wall. This is the time when female ball pythons are, for lack of a better way to phrase it, developing into beautiful, mature young ladies. Nothing to do but wait until she's done with her girl time.