A few things I left out.
The way I reproduced this was to force kill the RabbitMQ pods in K8S
The code I am looking at now, is just adding jobs to queue in a loop. I've created a single bunny object for this.
We I see the STDERR exceptions above. I also notice that two "background" threads from bunny go away. so when I am normally running I see thow threads like this#<Thread:0x000000000252c6d0@/home/myhome/.rbenv/versions/2.6.5/lib/ruby/gems/2.6.0/gems/bunny-2.17.0/lib/bunny/heartbeat_sender.rb:46 sleep
After I that STDERR exception, those threads are no longer there.
Oddly enough I do have "Thread.abort_on_exception = true" set, so I would off thought it would have exited my app out when those threads "dissappered"