It appears that the 'MSExchangeMailSubmission' service on server {2} has not yet discovered any servers with the Hub Transport ...

It appears that the 'MSExchangeMailSubmission' service on server {2} has not yet discovered any servers with the Hub Transport server role installed in the local Active Directory site with GUID '{3}'. This condition exists after the service is restarted and before a local mailbox submission is processed. This can also indicate that there is a problem with the service successfully completing 'MSExchangeADTopology' discovery.