I don't see the problem with this. If mail is sent to trouble just
prior to a shift change the shift coming on inherits the open trouble
tickets and the oncall engineer gets the escallation if the status
isn't updated within 15 minutes from the TT going open.
Part of changing shifts is changing the mail aliases for real time
response. I don't think there is an interim window where mail to
trouble or to the internal escallation gets dropped.
How is this anything but the most reliable contact information you can
get? Not the same person each time, but real time response from the
organization around the clock.