It seems outbound mail for some domains was not working following the reboot test. This has been fixed, all queued mail should be sent shortly.
Reboot test has been completed sucsessfully. 300 days since the last one, nice.
Hopefully should be ok whilst I'm on holiday now.
I will be performing a couple of reboot tests on Obelisk today and possibly tomorrow, to ensure that the server can survive a power outage whilst I'm on holiday.