Does it matter what registration values you assign to your aircraft? What I mean by that is will my pilots not be able to fly if the registration number isn’t a certain number on VATSIM?
Nah, there’s a general guideline on how registrations are done in the real world, you can follow that, or just assign any ol’ value to it.
The system doesn’t match up the registration with the schedule when you file a PIREP, so you can use any aircraft. The aircraft you assign to a schedule is just for reference