Light doesn't matter after the reversal step, because that fully exposes all the halides. Extra exposure makes no difference, so you could do the reversal and everything after (CD, bleach, fix) in light.

As to agitation, bleach+fix are to completion. If you reduce the agitation, you may need to go for a little longer to make sure you don't under-blix. The kits I've worked with (Fuji) recommend continuous agitation and they state slightly longer times for 5/30 agitation patterns.