Outbound DID


For 3 years I have sent outbound DIDs as follows:
exten => 911/1101,1,Set(CALLERID(number)=9999999999) ;9s reflect my DID
exten => 911,n,Dial(${TRUNK}/911);

AT&T now is reflecting only the billing number at the PSAP for all DIDs.
This is an Asterisk BE 2.5.1 system.

Nothing has changed on my system for some time in the way of trunks or stations, but I recently wrangled (and lost) over providing correct ALI data. Now I can’t help but wonder if something changed on their side in an effort to “help the customer”.
Can someone tell me if this is might be an AT&T issue, so I can fight another day, or am I overlooking something?