Daylight is a big one! This is called "photo period" and is a trigger for many birds to go into a reproductive cycle. It makes sense; most birds want to have their babies during periods of the longest daylight, in order to find a lot of food to feed them with. Since we keep parrots indoors, we usually accidentally extend their photo period by having lights on at night. One thing you can try is to make sure she gets at least 10 hours of true darkness each night.
This is incredibly beautiful, you really captured the bird's personality and intelligence. Furthermore, the painting style you selected is just stunning! As the owner of a conure, I take my hat off to you