From a filtering standpoint, it makes no difference. Some electric utilities offer lower rates at off-peak times. If yours does, then you may save some electricity $ by running it during those times.
BTW, you very likely do not need to run the filter that long (8 hours). Most people, including myself before I found TFP, run the filter much longer than needed. The
Determine Pump Run Time article was recently revised. It's worth taking another look at. I have cut way back on my filter run time and the water is still crystal clear. Proper chlorination and balancing play a leading role in water clarity.