How to swap user roles?

Summary:

We have a scenario:

User A has only GTM_ADHOC role(Default role assigned during user creation).

We want to change it to GTM_ANALYST role only and remove access to GTM_ADHOC role.

Can you please let me know other methods rather than just deleting and recreating the user with different role.

Content (please ensure you mask any confidential information):

NA

Version (include the version you are using, if applicable):

23C

Code Snippet (add any code snippets that support your topic, if applicable):