Update: I just did my late day test and now I have:

Free Cl 7.0
CC: 0
Total Cl: 7.0

Seems like an awful lot of chlorine drop from this AM when it was only sunny for half the day. However, my pool is very clear now.

So, for the very first time, I'm thinking of adding nothing this evening and retesting tomorrow morning.

If this level of Cl holds, should I think about adding more CYA? I think I can calculate my way into a 30-40 level with 4# already added.

Thanks for any advice.
Sandy