How long can I keep a clone in 4" rockwool?

Here is the jist, I'm designing a new grow room. My flower room will be running DWC buckets and I wanted to go straight from clone (in 4" rockwool) to my buckets. So the question is, how long can a clone sustain in a 4" rockwool during veg?

I'm trying to come up with the simplest process, clones into rockwool for 4 weeks, then into flower.

Or will I have to use 6" cubes? Or is there some other simple method to clone/veg into dwc?

Hmm... just realized I could put the 4" cubes into a 6 or 8" netpot that I will be using in my DWC setup and go for a top feed or ebb. What do you guys think?

Clone into 4" cube, into netpot with hydroton, then ebb flow or top feed drip. I should be able to easily take the entire netpot and slide right into my dwc bucket lid made for the netpot.