The permissions within roles are what determine the license level associated with the role, not the level of license in the subscription.
So, if there are Roles which require a PureCloud 3 license (especially custom roles) you will need to go through all of them and adjust the permissions to conform to the new level of license in the subscription.
I don't know for sure what will happen...there are default Roles which are tied to the level of Genesys Cloud licensed, so they might just go away and you don't have to worry about those ones, or they might stay until removed form all the users that have them assigned. Same for permissions in custom roles tied to the license level in the subscription.
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George Ganahl GCP (Genesys Cloud), ICCE
Principal Technology Consultant
Genesys
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