It's possible that still buried in legal agreements between network operators and Apple there's a clause requiring Apple to ensure Apple knows what behaviors the network operators' networks will endure when Apple issued hardware connects.

I wonder (and can not prove, but remember this concern at Qualcomm and Apple back around then) if the issue was forced by Cingular Wireless originally.

In particular, iOS devices were dependent on carrier cooperation, and Cingular may have required only vetted software builds to connect to their network.