Hey @P-E,
Welcome to our Community.
You can always switch back to a previous plan as long as that plan is still offered. If the plan is no longer in-market, it would sadly not be possible to get it back and you'd have to choose one of the plan options offered at the moment.
To take a closer look at your account and old plan, you can reach out to us here or we can send you a PM on the Community.
Let us know what you prefer 
