I've exhausted my googling on this topic and hoping someone has experience doing something similar!
I just finished an Exchange 2010 to 365 Hybrid migration. We are using DirSync and plan on keeping it running. I want to now stop the hybrid and uninstall Exchange 2010. I know the steps to remove the hybrid connection, the problem comes when uninstalling Exchange. I have heard it will remove the proxyaddress and other key mail-related AD attributes.
How can I remove Ex2010 while keeping these attributes? Will installing Exchange 2013 help at all (and then uninstall it)? I think I read somewhere a hybrid Ex2013 can handle an uninstall while keeping these attributes.