I wrote in my post that the clearance limit was the airport. It is cut and dry if the clearance limit is IAF for example, then one would have to hold until further clearance. Lets take 2 cases:

1. VTF approach. Pilot mus get approach clearance to turn inbound and track as well as descend as published.

2. Pilot Nav approach. When is the cut and dry point here if the clearance limit is the airport? I do not think their is one. At least I have not found it in the AIM yet.