I'm using hyperledger fabric  1.4.9 and my admin certs and tls certs of ordererers expired.  I also raised the issue on jira.
After enrolling new admin and tls certs i try doing this :- 

Do config update for orderer 1
Restart it with the new certificate

Do config update of orderer2
Restart it with the new certificate
...
...

Do config update of orderer6
Restart it with the new certificate

but the moment i restart my orderer , it looses consensus and never achieves it back. 

I'm stuck on this for past one month now and my network is in production. i feel like I am seriously stuck now. 

please help as our product is also listed on hyperledger.org.