The ability to use override codes is declining. While RBOC digital switches allow for it, packet switches generally do not.

For example, I am 14 year Verizon Fios subscriber. Up until last year, I could enter override PICs...1010288, 1010222, 1010333, 1010444. During those years I was being serviced by Verizon's local digital switch.

Last year, I upgraded my services. One change was to migrate my voice service from Verizon's local 5E to a packet switch. The packet switch doesn't allow a 7-digit override, 700 test number or ANACs.

Verizon Digital Voice service is all Verizon (local & long distance). I can't speak for AT&T, Consolidated or Frontier.