Upgrading Active Directory & Exchange 2013 enviroment

Hi,

We would like to upgrade our Active directory and Exchange Email systems to its latest version.

Let me give a brief about our enviroment.

We have 6 Active Directory servers, 3 Client Access Servers and 3 Mailbox Servers (DAG). The email setup is hybrid

(60% mailboxes in Office 365 and 40% is on premises)

We are planning to upgrade it to 2016.

I request your comments and feedback about the best practice approach for performing this activity.

If any one have a valid document ,kindly share to my personal email ashruakkode@gmail.com

Thanks & Regards

Ashraf

Ashraf