Plugin registration / serial number question
I'd like to write a single plugin that can have subsets of functionality individually unlocked via serial number. For instance, a user initially purchases plugin featureset 1. When they register the plugin with the provided serial number, only featureset 1 is activated. Later they purchase featureset 2, and are given a second serial number. After adding this serial number to the plugin registration featureset 2 is unlocked.
Is this approach possible in the plugin registration/serial number framework, or would I be better off creating separate plugins for each featureset? I see in the SDK docs that it is possible to have multiple registration prefixes for a single plugin. However I'm not sure if this means that the plugin can carry multiple serial numbers, or just a single one from either prefix. I also don't see anywhere from within the SDK to ask what serial number(s) my plugin is currently registered with.