We have a F617R3-FT that is stuck af BF .As soon as I connect the power cables and turn on all nodes without pressing the Power-On, but leave all the nodes are locked in post with the message BF.
If I turn off and relight the message disappears and the nodes complete the post starting of the engine.
You can update the IPMI firmware. Please apply the latest IPMI firmware (2.21 or later). This will solve this behaviour.