Thanks for the super-quick reply! Oh my God, this board just keeps getting better! 
Yes my motion detector runs on 12v, as well as the sirens. I didn't realise they could all operate off the board's 12v power supply! When wiring it all up, do I need to also connect a diode to prevent damaging the board? (or have you already designed it not to require a diode?)
I'm guessing that I'd need to connect the board's 12v power supply in serial with the two 12v inputs that sit alongside the outputs? (sorry if that sounded confusing)
And my HA server doesn't have a RS485 connector... This seems like a pretty roundabout way of doing it but could I use a RS485 to USB adapter to connect it to Home Assistant? (Hmmm. Actually surely I'm missing something, because the existing USB-C connector should be able to fill that purpose?)
Are any of your other boards likely to be going on sale anytime soon? I can't use Wifi where I live sadly, so your board's ability to function totally wired is fantastic. (especially in a security sense!) It would have been lovely to have an inbuilt buzzer on the A16...
Are you planning to make any in future that might operate via PoE power? Having 12v power supplies isn't as neat as being able to connect and powering the board solely via that ethernet cable!
Yes my motion detector runs on 12v, as well as the sirens. I didn't realise they could all operate off the board's 12v power supply! When wiring it all up, do I need to also connect a diode to prevent damaging the board? (or have you already designed it not to require a diode?) I'm guessing that I'd need to connect the board's 12v power supply in serial with the two 12v inputs that sit alongside the outputs? (sorry if that sounded confusing)
And my HA server doesn't have a RS485 connector... This seems like a pretty roundabout way of doing it but could I use a RS485 to USB adapter to connect it to Home Assistant? (Hmmm. Actually surely I'm missing something, because the existing USB-C connector should be able to fill that purpose?)
Are any of your other boards likely to be going on sale anytime soon? I can't use Wifi where I live sadly, so your board's ability to function totally wired is fantastic. (especially in a security sense!) It would have been lovely to have an inbuilt buzzer on the A16...
Are you planning to make any in future that might operate via PoE power? Having 12v power supplies isn't as neat as being able to connect and powering the board solely via that ethernet cable!