I reached out to their support last time and the following was their answer.
Hope this helps:
If you want to keep the old board you could use an Interface kit. However, it will be only able to read one the zones on a doubling senario. And I’m not sure that board could be setup for a programmable zone to monitor the status of the alarm or a keyswitch for remote arm/disarm.
In that case, I’d recommend a Conversion kit. It would be simplier and allow you to use all the zones as well as full control. However, you will lose the old keypad.
Exactly the same scenario here. Having Hills Reliance R8 unit with 6 zones configured. Planning to get Konnected Alarm Panel Pro kit, will it work at all?