Need to know max current draw for each rail. Have 8 servos that will be connected across the main and aux rails. Each 5V and can draw up to 1.8A of current. Only two servos will be moving at a time, the rest are idle (Idle current <10mA). Need to know if I can connect BEC to one pin of MAIN and AUX rail, and power the servos from these rails
Yes, that’s exactly what you’re supposed to do. Provide enough power on the rail.