Every Monday all of our phones are down saying "invalid account"

Recently we found that our FreePBX system was not auto updating each week. We went ahead and set it up to auto update on Sunday mornings. Since then, every Monday when we arrive to work all of the phones say “invalid account”. The fix is to simply reboot FreePBX. The update log seems to show everything went fine with the update. See update log below. We are running FreePBX 13.0.192.16.

No update currently running. You may close this window.

2017-08-13 00:00:12: (10.13.66-21) Requesting updates
2017-08-13 00:00:13: (10.13.66-21) Processing update
2017-08-13 00:00:13: (10.13.66-21) Now running 10.13.66-21 script
2017-08-13 00:00:13: (10.13.66-21) Starting stage 1
2017-08-13 00:01:57: (10.13.66-21) Stage 1 complete
2017-08-13 00:01:57: (10.13.66-21) Starting stage 2
2017-08-13 00:02:36: (10.13.66-21) Stage 2 complete
2017-08-13 00:02:36: (10.13.66-21) Stage 3 complete
2017-08-13 00:02:36: (10.13.66-21) Starting stage 4
2017-08-13 00:02:42: (10.13.66-21) Stage 4 complete
2017-08-13 00:02:42: (10.13.66-21) Starting stage 5
2017-08-13 00:02:42: (10.13.66-21) Stage 5 complete
2017-08-13 00:02:42: (10.13.66-21) Starting stage 6
2017-08-13 00:02:42: (10.13.66-21) Stage 6 complete
2017-08-13 00:02:43: (10.13.66-21) Upgrade script complete
2017-08-13 00:02:45: (10.13.66-21) Upgrade process successfully completed!

Any ideas?

Thanks,
Darren

The log shows the successful update. What happens when the phones try to reconnect?

The update ran just after midnight Saturday night. We were closed all day Sunday. When we arrived to work Monday morning all the phones were not working with the message on the display saying “invalid account”. This is an exact repeat of what happened the week before. More than 24 hours after the update, the phones still say “invalid account”. We have to reboot FreePBX to get them to start working again.

We have had the same occurrence on two sites here. For the time being, auto updates have been disabled, we now do them manually about once a month. It is also our policy to wait about 30 days before applying updates to a system in use as one time an update caused a whoops and SSH was the only access for the fix.