400 for 2 weeks, 600 for 3 weeks, and both til finish.=P but of course I know nothing of your ventilation issue.

And for my opinion to your question.:jointsmile:

I'd say the more mature plant that already has flowers and plenty of resin on them will reward you more under the 600 until finish.

Consider just a smaller add on of a flower room for the 400? Maybe a clone SOG table? :jointsmile:

Veg enough large plants to overfill your current bloom room, and cut them back enough to fill your 400 SOG table.

Or just do the 400+600 super scrog in your current room.=P

Either way, I've had many many :rastabong: rips and I'm just not finding a closure for this response. :stoned:

beSafe