Your numbers are fine. With a cya of 40, just keep your chlorine between 3-6 all the time. When you let it dip below 3 is when you risk starting an algae bloom. Watch your ph. Anywhere between 7.2-7.8 is good. Below 7.0 is acidic and can damage your pool. Your alk is a little high, but shouldn't cause any problems. Ignore what the pool store says about chlorine lock. If your numbers are good like yours are, and the water is sparkling, go swim and enjoy your pool. Hope this helps.

BTW FC + CC = TC always.