So when I was a kid , I used to spend a lot of time phreaking and playing from a Pacific Northwest Bell line. Back then, in the early 70s I made an odd discovery that haunts me to this day. This was a Portland, OR line when the entire state was 503 area code.
Officially (503) 922 NXXX was assigned to Umatilla or Pendleton Oregon which was at the other end of the state, and long distance from me in (503) 777.
I discovered however I was able to dial 922 XXX (just six digits , when 7 digit local dialing was required) and it would ring and I would get an answer often times. Now I was in the (503) 777 prefix when I used to play with this most but I am almost certain that it also worked from other prefixes as well. I might have considered this a carryover from 5 digit dialing such as was used in Seaside Oregon at least until the 1980s , however there was no 792 prefix in Portland at that time that I was aware of. Maybe however the 922 was pre-pended with a 2 which represented the first digit of the majority of Prefixes in Portland? This would have possibly meant that these calls were going to 292 prefix on the other side of town?
So this remains a perplexing question that maybe some old phone guy here may have some insight into. I am very curios to know why this was the ONLY prefix I could dial 6 digit numbers on and where the hell those calls went.
Thanks
Mark