Last night I unplugged my modem and router to rerun the wires so I could plug them in my UPS and the whole thing took around 15 minutes. I have the network supervision enabled and for some reason I only received the SMS and email about 5 hours later and it took an extra hour to get the "UP" msg.
Last time we had a power outage I noticed that the timestamp of the SMS didn't match but I didn't bother but now I'm thinking it might do the same with an intrusion alarm, which would be more critical!
Envisalerts are issued within 1 second of the actual event. If there is any delay it is on your carrier's end. If you submit a support ticket we can look up the actual transmission log to tell you when your alert was accepted.