Hi Thomas,
As per my understanding, this applies to the SSID.
I think the best option is to have this controlled via switches in case your switches support some kind of POE based time-range.
Switches can turn off the POE on the ports where AP's are connected based off the time range profile that you configure on the switch itself.
Without POE, AP will be compleltely down.
I will also try to check in parallel if the time-range on IAP can help in stopping RF transmission completely.