Endpoint Protection Small Business Edition

I am currently running SEP 12.1.1 on premises and have been told that I will need to migrate to SBE (either on premises or cloud version) now. I would like to go ahead and move to the cloud version to accomodate Windows 10 desktops next year, but I am confused about which steps to do. My licenses expire in a month. Do I need to purchase my new licenses before I migrate? Also, after I migrate, do my clients automatically update or will I need to reinstall? What about my Server - will I need to uninstall anything on it? It runs the client as well as acts as my SEPM now.

Here is there migration site:

https://www.symantec.com/page.jsp?id=sbe-migration

You can do this when you go to renew pricing:

https://www.symantec.com/content/en/us/enterprise/other_resources/eol-overview-sep-sbe-12-1-sps-sbe-4-0.pdf

Just beware of the price increase.