I need Remotedesktop with 20 user, have a cal for 2012, but windows server 2012 essentials does not use license and only permits 2 user

if you transition from windows server 2012 essentials to windows server 2012 standard.

article "transition from windows server 2012 essentials to windows server 2012 standard"

technet. micorsoft.com /en-us/library/jj 247582.aspx  Pretty simple process ( of course I will buy the license key for 2012 standard)

Will I be able to use a 20 remote deskop user cals  by just doing the transistion process.

OR will the 2012 essential limitation of 2 rdp users remain?

If so I guess I have to completely rebuild the server, install a clean copy of server 2012 standard from the beginning?  Or is there an upgrade process that would get the 2012 essentials completely off the server.