We got about 5 inches of rain yesterday. My water level is about one third of the way up my coping. My pool is still open and pump running as normal. Not closing for about another month. Any reason to lower the level?
It could also get in between the setting bed for the coping and the top of the pool wall and affect the bond of the coping. It would take prolonged saturation, and it isn't real likely, but if there are voids or compromises beneath the coping it could cause problems.
Better safe than sorry, so just drain it down. If there is a hose bibb on your circ pump, just attach a hose and run your pump. That will pump it out.