Having four qualifying used to get you "Priority Access to Vehicle Software Updates." It is different than the Early Access Program they are offering which is beta testing before public release of an update. Personally, I would prefer to be offered Priority Access than the Early Access Program but I will be surprised if they do follow through with either.
@brkaus - Do you find having Priority Access actually gets you updates early? I have seen people mention they should have Priority Access but never seem to get updates any earlier.