I run a hybrid exchange environment with Exchange 2016 and Exchange Online. I have a maintenance event coming up with my on-premise exchange server where it will be offline for a few days. I have 2 questions:
1. My on-premise exchange 2016 server still currently houses all my distribution groups that are internally and externally available. All of the user mailboxes are in Exchange Online. If I shutdown the Exchange 2016 on premise server, will the distribution groups still work if my hybrid setup is configured properly?
2. If I flip my mail routing to flow through Exchange Online first, will exchange online deliver messages with a destination for the on-premise exchange server?
Thanks in advance.