Seems like around this time during summer every year, we get a 'Hi salt' (chlorine generation halted) reading and have to partially drain and refill the pool. Does water temp or evaporation effect salt concentration? We are in southern CA, water is very expensive. Is there another way to reduce salt concentration? Salt reading has been perfect (around 3300) for the last few months.

15000g in-ground pool
Aqua-rite swg 6 years old
salt cell 5 months old
water temp is 79 degrees

Are you verifying the reading with an independent test of your own - (strips or the taylor drop test kit)?