Delete group when a user buys an upgrade?

[Myck]

Hello, I need help please, I tried to do it but it was not possible, I also searched the entire forum and I did not find something similar to my case.

It is about group promotions, then I will comment on the context.

I have the following User Groups:

Free
Basic
Premium

I am using an addon that automatically adds to the "Free" group when a user registers.

I have 2 paid User Upgrades available :

Basic
Premium

When a user purchases a Basic upgrade they are...

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Delete group when a user buys an upgrade?

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