I bought large mealworm at the end of June. They stayed in a hot car for several hours and that week many started to pupate. Now, a little less than 3 months later I have beetles hatching from what I believe to be babies of my first set of worms. The original hatch beetles are still alive and I have many medium worms and apparently they are pupating but I'm having a hard time finding the pupa. so it is house temp which I set therm. at 77 but I have them in the 'warm' room which is a few degrees warmer. Many of the worms are still smallish so I'd say 3 1/2 months I'll know more in 3 weeks which would be more like 3 1/2 months. Hopefully as the number of pupa increase they will be easier to see got alot of frass.