With a hybrid deployment, some users will have %BRAND_EXCHANGE_ONLINE_SHORT% mailboxes on-premises and some users will have ...

With a hybrid deployment, some users will have %BRAND_EXCHANGE_ONLINE_SHORT% mailboxes on-premises and some users will have %BRAND_EXCHANGE_ONLINE_SHORT% Online mailboxes in %BRAND_OFFICE_365_SHORT%. As part of planning and configuring your hybrid deployment, you need to decide whether you want all messages from Internet senders routed through your on-premises organization or through the %BRAND_EXCHANGE_ONLINE_SHORT% Online service in %BRAND_OFFICE_365_SHORT%. The path messages take depends on how you decide to configure your MX record in your hybrid deployment.