Hybrid Exchange setup with Exchange 2013

Hi,

A customer is currently running on-premises Exchange 2010 and 2013 with Exchange Online Protection (EOP). All Emails flow through EOP to on-premises Edge Transport 2013 Server. When they setup EOP they used FIM 2010 R2 for Active Directory Synchronization.

Customer wants to evaluate Exchange online and we are planning to deploy Hybrid Exchange Infrastructure. We want to know that is there a way to upgrade FIM 2010 R2 to Azure AD Connect? or can we setup additional Directory Synchronization server for Azure AD Connect tool?

or can we leave FIM 2010 R2 as is for Directory Synchronization? or is there any better approach?

Thanks, Sheeraz