I just encountered the same problem on Mighty 4K. I had a strong suspicion that Chitubox was taking both light-off delay and rest time and applied whichever was higher. So I changed waiting mode to "Light-off delay', set it to 5s, which is obviously less than a full lifting cycle, then changed it back to "Resting Time" and sliced the model. As expected, it began to wait for 2s after retract, just as I wanted, instead of ~10s as it did before.
