Queued builds not showing in the build queue, not being picked up by agents

Builds on BEAC are not being queued. On the "all plans" page, the icon is the blue queued icon. However on the "current activity" page, there is nothing under queued, and nothing under building. After a few minutes the builds are aborted and go yellow.

Looking in the system errors I see:
"Build RELENG-RELENGDUMMY1-JOB1-57 had to be cancelled: it was marked as queued but was not present in the queue for (at least) the past 210 seconds."

Popping up for each build.

This is only happening on BEAC, the other bamboo servers are fine.