Is there a way to have the pump relay turn on only for specific zones

I have a gen3 sitting in the box and can’t use it. I’m looking for the same feature as many other’s here. I have an injection system that runs on all zones but only on Fridays. My current KRain Pro controller has A,B,C programs and you can assign the pump to the program (not the zone). You say you wrote a simple script? Where does this script run? Is there any way to achieve pump on/off specific to a schedule or program as apposed to a zone? TIA