Winter closing IG BBB Safety Cover - Best Chemical Balance prior to closing?

[blue wolverine]

My first post. I use BBB. My pool is inground cement with epoxy paint over concrete. I use BBB method. Well Water, some iron. This year have only added CYA in the spring, liquid bleach 12 %, and muriatic acid to lower ph.

My pool is approx 28x18 inground kidney shaped.

Current CYA 30, Chlorine shock level, PH 7.8 Calcium 140 Water 75F

I will be closing next week, putting on solid safety cover.

Finally the question,

What is the best chemical level prior to closing?