It's very rare for them to go down. I think I can remember one major outage during business hours in the last few years at which point we just switched to manua

It's very rare for them to go down. I think I can remember one major outage during business hours in the last few years at which point we just switched to manual monitoring for the few hours. If that is within your outage model, you'd probably want a redundant on-call service I suppose, even if it's just escalating to a single known email or sms group.