Hi there, and welcome to the Forum.
How high have you had the humidity, j.a.m? quails need to beincubated dry, ie in the UK no added water as the atmosphere will reliably provide the 45% they need and higher humidity has adverse effects. Then wait until eggs are active and pipping before upping the humidity to 75%. Temperature should have been 37.5C, down to 37.0 whilst hatching.
CPQs should have hatched by Day 16.How are you counting the days? The first 24 hours in the incubator are Day 0, then Day 1 is when they have had one days incubation and so on. So it may be yours are actually on Day 15 at the moment. Have you stopped the turning and lined the base with nonslip material eg rubber matting or cotton cloth, to prevent splayed leg? They should be rocking and twitching by now or in the next 24 hours. Hatch times do vary, if yuor inci was perhaps set a bit cool they may be later. Dont disturb them and dont candle them again. Most people dont candle quail eggs anyway, the patterns make it difficult especially with tiny CPQ eggs, so not reliable, and anyway its best to reduce disturbance during incubation as mnuch as possible.
Please let us know how the hatch goes. Looking forward to some photos of your little bumblebees!
Get the brooder ready and well heated up to 37.0C beforehand.