This article from the documentation is a good start: Migrate from Core-Based to User-Based Licensing. But then this thread from the community is a GREAT resource: Just when I was sorta-kinda understanding the new permissions of 2018.1 I read this...
Hope this helps!
Thanks Santiago. The articles help.
I am still not sure, if there is a cost associated to a server licenses or not with the new licensing model? Do we have to pay the annual server maintenance cost or not? If not, will we pay only the cost for the users we have?
Note: We have user based licensing as of now.
I'd encourage you to talk to your Tableau Sales Rep as he/she will know of your particular situation best. Broadly speaking, your licensing won't change unless you chose to do so. Assuming you are in a perpetual model, you'd continue to pay the usual maintenance for existing users.