Please excuse if this is a stupid CBSubs newbie question, but I can't find anything anywhere else about this.
Say I have 3 plans. All are concurrent = non-exclusive. Each individual plan can be subscribed to only once per user.
A user shall be able to pick any single plan or any combination of multiple plans.
If he picks one on registration, he shall be able to add another one (or 2) later on.
So far, so good: I set all plans accordingly and under top level, and it basically works fine.
But it appears that all plans must be set so they can be upgraded to, otherwise they are not displayed anymore for the user. Promptly the system treats them as "upgrades" everywhere... which in this use case they aren't. In fact, there is nothing to "upgrade" from or to, the 3 plans are complete separate, not variations of each other, and not related to another.
Is it just a language (override) thing, or am I doing something wrong in setup? Should I rather consider setting up a parent and a child for each plan, then somehow hide the parents from the plan lists (because I guess children of different parents aren't upgrades to each other)?
A brief hint would be greatly appreciated - thanks!