I was wondering about that myself. You can hear some rather interesting consequences of this on one of the numbers I posted in the some numbers thread.
You know what I think it is, though? I think the equipment might've died. Within the last year or two, my calls to it would randomly fail. Whenever I was scanning former Bell Atlantic/NYNEX exchanges, I'd always check CBCAD recordings and echo tests twice, since more often than not, it was just the AIS fudging the call.
I originally thought it died, but it might not be the case since New York never had this intercept system, but now they have the same recording that's now in places that ran the system. Or, maybe Verizon wants to standardize things. Could it really have been a centralized system for so many states?
Over the past year, I got a lot of busy signals instead of AIS reports. That never used to happen.