How replace a reseller licence with a Plesk licence?

We would like to trade "web host edition" licences in existing Plesk installations. We are currently using licences from a Plesk reseller. These do not include support from Plesk. We want to replace the existing licences with licences that we lease from Plesk directly to get access to support.

Can this be done trouble-free or will a change in the licence file/licence information break functions of Plesk?