Is the Teams tariff an update or rather an additional service, can I opt-in and opt-out without losing my anterior pro GPTs , chats and data?

Is the Teams tariff an update or rather an additional service, can I opt-in and opt-out without losing my anterior pro GPTs , chats and data?

Due to 30 yrs of experience in IT, i want to know beforehand how the technical details of testing the Team version is because it’s a lot of money as a single entrepreneur, and i want to add a friend with who i sometimes work with, and I don’t want him to lose his data or access to his GPTs or chat history even if he decides to opt-out after trying.
The information i could find sometimes talks about upgrade, then it talks about adding (as in additional) , so I don’t feel secure risking it yet. Which is strange talking about a high tech language centric service with 100 mio users :slight_smile: - so this is my shoutout: how are the concrete and realistic effects on my current GPTs, chats and Data if I change to Teams and potentially want to switch back to Pro? Also: is there a minimum time after up- or downgrading or any other limit or consequence?
This is my first question here, thanx a lot to everyone reading this.

I read about a transition process, but is that transition/transcription necessary? Do i have the option to run Pro for me privately and Teams in parallel for work? - maybe running on different browser to have the sessions separated?