You can set the circulation pump to run 0 to 24 hours. Even at 0 hours, the pump will still come on for 2 hours at midnight.
The circulation pump will indeed shut off if the temperature gets 2 degrees above the set temperature. This only occurs if the water is over 95 degrees. For example, the tub is set for 80 degrees and the circulation pump is set for 24 hours on a hot day. The circulation pump will continue to run until the temperature gets to 95 degrees.
The main pumps come on 4 times a day and run for about 2 minutes.
The pumps on the 880 models are now 2 1-speed 56 frame pumps.