Prior harvest flushing when picking buds at different times?

I've been too greedy on this grow, haven't some cola's really packed. So, as it seems, about 40% of my plant is going to be ready next week because it got better light while rest should take 2 more weeks i'd say.
Question is... what to do with flushing?
If i'll flush for the early buds can I harvest and then give another nutrient shot and start flushing again?....

thanks