My experience with the XR 4046H has been about 15-20min regen. The temp light stays on a few minutes longer after the regen light goes out to show cycle is complete.
NH TL-100A with Bush Hog 5045 FEL, WR Long 3rd function, LS XR4155HC w/FEL, WR Long 3rd Function.
The temp light comes on at start of cycle indicating that system is coming up to temperature. It stays on after regen. cycle indicating cool off. My cycles, on XR4046HC, are about 20 minutes.