During the last few days (sorry I cannot be more concrete) wikibugs has stopped showing comments from phabricator tasks on IRC (confirmed at least on #wikimedia-operations and DBA)
The only way to get it working has been to manually restart it. After the restart it immediately comes to back and start working normally.
All the time I have done the restart, the output of qstat has showed jobs working, so they were there but apparently not working.
I have not been able to find any error on the error log, apart from this - which happened after a restart:
2019-12-19 06:07:58,792 - wikibugs.wb2-grrrrit - ERROR - Error, probably SSH connection dropped.