Symptom
During an ASCII replay of the configuration, BGP configuration may be applied in the running config but will not work correctly. An error message in the form of "The BGP instance is not in expected state" will be seen when the router attempts to replay the BGP config.
Conditions
Can occur on an ASCII replay of the configuration (typically when upgrading from major software versions)
Workaround
Remove and re-add the BGP feature (ie, "no feature bgp" followed by "feature bgp" and the pre-existing config)
Further Problem Description
This is a timing / race condition. It is rare, but cannot be predicted.