Hey Andrew,
Sarnia has a similar system as well. It sounds like there is no real “on-call” system anymore. 10-15 years ago we did have an on call list, where FPO’s got paid to be on call, but now communications calls one of our three investigators when needed. We are not required to go either, but of course it is much appreciated. It’s nice to be able to talk to the crew who fought the fire, but investigation is a daylight kind of a job in my opinion.