Previous setup was an Exchange 2010 environment. Two CAS servers, two Mailbox servers, and two Edge servers.
I prepped the domain for an Exchange 2013 deployment and installed two CAS servers, two Mailbox servers, and two Edge servers. I also setup a DAG for 2013. I can manage the entire Exchange environment from the 2013 install and have been successful creating mailboxes and DL's in the 2010 environment from the 2013 servers but no mailboxes have ever been migrated to 2013. Everything still sits on Exchange 2010.
We are now moving in a different direction with our domain structure and I need to remove 2013 without harming our current 2010 setup. Are there steps I can reference to safely uninstall Exchange and clean up the aftermath in AD?