Exchange 2016 to Office 365 migration process is widely processing nowadays. The reason is simple; Office 365 is cost-efficient and has user-centric services like Skype for Exchange, Hosted Exchange Server, etc. To migrate, users have various manual methods such as Cutover migration, Staged migration, Hybrid Migration Method, etc. 

Cutover migration supports Exchange 2003, 2007, 2010 and 2013 and useful for mailbox numbers less than 2000. Staged Migration supports Exchange 2003 and 2007 and appropriate for medium-sized enterprises and Hybrid Migration supports Exchange 2010 and 2013 and good to migrate 150-2000 mailboxes in small batches. 

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