> An important component of credit courses is the time limitness

Huh? Why would that be an important component?

I mean I know that it's typical for courses that come with credit, but in my mind it's just a side effect of the administrative side of providing courses, not something that's at all central to accreditation. I.e. if you build up the knowledge over a longer period (which you can still do with e.g. resits) that's completely fine as well.