I don't keep peacocks, but since no one else has responded to your question, I'll give you my experience with mouth brooding tanganyikans...
Usually I can get fish to spawn within 30-45 days of spitting fry. I don't strip my fish, so fry are held full term by the mother. This window could probably be shortened if I was stripping. If fed well, with enough proper protein, and kept in clean water, 30-45 days is reasonable to expect, sometimes sooner.
I don't do anything to induce spawning. IME, if the fish are well conditioned, water is clean, and there's no stressors then the fish will spawn w/o any manipulation. I've heard of people dropping and raising temps, and adding extra water changes though I've never done any of that. I think these things hold true for most mouth brooding African cichlids.
Other species that only spawn a few times a year, that are triggered by certain environmental changes may require a bit more tinkering to induce spawning, but not peacocks. Good luck!
