I feel ya, seems like I've been waiting forever lol! I have 4 large Cheyenne pods that are almost all red I don't want to cut them to soon though.
Randal

I've been staring at green pods for weeks upon weeks and I'm finally starting to get flushes of color, slow at first but now its becoming a lot. I'm really starting to really see what I planted and realizing why everyone looks at me like I'm crazy when they see my garden. Do I regret any of it, absolutely not, will I do it differently next season, absolutely! Bigger!! haha

But to answer what cues that change.... I have know idea. Its like the watched pot. Peppers are shy.

I think when the fruit (like tomato and pepper) reach a mature size and starts changing color , it does not need any help from the mother plant. If you check the stem, it is almost hard and woody.
The ripening process is an internal change inside the fruit. I have purchased different peppers with a hint of color, let it sit on the counter and they turned beautiful red ( Serrano, Jalapeno, shishito, Gypsy ...). And I have saved seeds from them and have planted and all have germinated. Also, flavor develops while air drying a hot pepper.

I bought a Burpee "Sweet to Spicy) Friday that had one green pepper on it. Re-potted it and now it is almost completely red. One thing the label said that seemed odd id it said it would be more spicy green than red (that said only about 300 on the scoville scale. I'll be eating it in the next day or two and see. other than that everything is still green