Josephine That coincides roughly with the time that I rebooted the host server.
The server's been pestering me about pending upgrades and I finally decided to just update and reboot it. I kind of like having infinite uptimes on my machines, but these days it's not very advisable to forgo the reboots especially if security patches are involved.
The update itself did restart the docker containers, so that would have been interruption number #1. Then the host reboot would have been interruption number #2. Both ought to have been very quick < 30 seconds, but that may have been enough to interrupt long running API polling and such.