The thing is that there is a check in cbsubs (and i verified the code and we re-tested it) that makes it impossible to delete plans with subscriptions in cbsubs since the first release, so i'm still wondering how that plan disapeared.

So I'm really stumped how you could delete the plan. By which exact steps did you delete it ? . Backup your database, and try it with another plan having subscriptions. It won't let you do it, and an explicit error message appears as quoted in my previous post.

The question here is not if those two issues are related, but that I don't trust the database state to be consistant here. And other database inconsistencies can explain that your settings don't work on your site, while they work fine on other sites and in our tests.

So the first step before troubleshooting further is to check the database consistency. CB Tools -> check CB plugins Database does fully check for database structure consistency, but not for data content consistency.

And that's the first work that would need to be performed manually, because if plan is missing while it should not be able to be missing, then other things could be missing too. I'm not going to spend time troubleshooting settings of install as long as i have not gone through database data consistency after that plan missing incident, unless we can reproduce that it can be deleted by a method that i'm not aware of.

i'm never 100% positive until the culprit is found and has admitted its bug.

But I'm not going to spend 4-5 hours for free (and off development tasks) checking everything and troubleshooting if there is a consistency doubt, or another possibly associated bug:

Thus, before anything else:

How exactly did you delete the plan ? which very exact steps ?
Are you able to reproduce using those steps to delete a plan with subscriptions in place ?
We need to be able to reproduce.

To answer your question:

Free users of CB will be kept if you uninstall + delete cbsubs tables, but memberships, and all payment records, and settings will be gone.

But please do that only after having reproduced and listed one by one ("click exactly here") the steps to delete a plan with existing subscriptions...

Thank you for the description and detailed steps sent by PM.

Uninstalling CBSubs and all tables starting with jos_cbsubs_ in the database, then doing a fresh install will bring you back to a clean install state.

I don't think you need to reinstall CB for this promo+tax issue you have.