New Board has no AUX+ that I can see

Hi all. My (very) old wired alarm system died, so I decided to try replacing it with a konnected board. It's only got 5 zones, so I got a 6-zone kit.

However, the new kit has a 3-pin connector in the bottom-left of the board, containing: AUX - | Alarm + | Alarm -

Should I use 'Alarm +' for my AUX+ wires? Or is there something I'm missing?

OK, I found this comment from Nate on the Home Assistant forums (which searching for stuff about 4-wire UK bells/sirens):

In it, he refers to 'AUX/ALARM+', so I'm guessing that it's a common 12V positive terminal for both the alarm and sensor (aux) connections.

So I shall consider this 'solved' least until my Raspberry Pi arrives today and I finally find out if everything works.  :D