The bees need 1.5 boxes of space to work the nectar for each box of ripened honey that is made. If you want 2 boxes of honey give them 3 boxes.
As for how much to give them for how long, that depends entirely on the type of crop that is yielding and the strength of the foraging force of the hive. My mid summer flows on any decent hive is capable of filling a 10 frame deep in 4 days. I take 2 boxes of honey off and give them 3 completely empty ones all at once. 7 to 10 days later two boxes are full ready to harvest and the third is mostly full but not quite yet ready.
The point is they need extra space to work and if you do not give it to them you are losing out on honey-money production capacity.
So, you see we really cannot properly answer your question because we do not know the strength of your hive(s) nor do we know your forage and flow conditions.
Location matters on this topic and the best place and persons to ask about seasonal flows and box fill rates are members of your local beekeeping club.