The dichlor will add 9 ppm CYA for every 10 ppm FC so if you are tryng to clear a green pool dichlor is a good choice since it dissolves (and therefore adds CYA) very quickly! You don't really have to wait for the CYA level to come up. It is there as soon as the dichlor dissolves (which is usually before it can hit the bottom of the pool when broadcast on the surface of the water.) Just shock with the dichlor until the pool is not longer green. If you have no CYA in the water your 10 ppm FC wion't last long and if you are still clearing the pool it won't last long either!

Dichlor is going to get CYA in the water much faster than adding CYA so if you need some in the water fast (and also since you have the dichlor on hand) I would suggest using it.

In a 22000 gal pool each pound of dichlor will raise your FC by 3 ppm so using 10 lbs total over time will get the CYA to just under 30 ppm (27 ppm to be exact). 11 lbs of dichlor will get raise the CYA 30 ppm so by using a total of 11 lbs to chlorinate and shock with instead of any other chlorine sources will get your CYA up pretty quick.