@timcharper: thanks for sharing your work. If your zones/stations are ‘sequential’ (which is so by default), then when you use the manual program API call, it automatically queues all the stations. Basically the scheduler makes sure the ‘sequential’ attributes are obeyed. What this means is that it you manually turn on zone 1, then zone 2, and so on, zone 2 will be pushed to the queued and will only run after zone 1 finishes.