That I can remember back in the 1970s era (pre-divestiture, of course), during storms, floods, etc., dialing '0' for SCBell/AT&T Operator Service (using TSPS back then), if there was heavy calling, you'd get the same type of recording.
New Orleans was one of the first places to have TSPS (Traffic Service Position System) automation for Operator Servvice, back around 1970 or so. But automation for operator type services even goes back to the early 1960s with TSP (Traffic Service Position) and even late 1950s with PPCS (Person to Person Card Special) in some parts of the midwest and northeast.
I forgot to add something about the old Cord-Board days ...
With the automated appliques for Operator Services, TSP, TSPS, TOPS, OSPS, etc., callers can be held in a queue. You can queue up more callers than there might be operators available to assist immediately. Today that is even more so since many LECs (and AT&T) provide touchtone/voice menu applications for automated operator services.
But back in the cord-board days for dial-0 operator services...
Calls to 0 just kept popping up on manual boards until operators could be available to plug into them to answer them. Of course, trunks to the dial-0 operator center from individual central offices might be limited as well. But if you could get a trunk to the operator toll board from your local central office, you would just pop up on the board until some operator there could plug in.
In 1980/81, I lived in Spokane WA (Pacific Northwest Bell, pre-divestiture, and before the early 1960s it was part of Pac Tel & Tel along with Cal). Remember in May 1980, the volcano in southwest WA (some 300 miles away) blew its top. Ash was spewed mostly eastward. This affected numerous parts of the US and Canada eastward from Washington state.
Other than those in the immediate area of the volcano, there was no real property damage or loss of life.
But trying to get telephone calls to points outside was difficult. Spokane WA at that time still had a cord-board for local/toll operator services. There was still a #4A Crossbar toll machine and it still used a photo-mechanical card-punch reading system for routings/translations. It did not even have an ETS (Electronic Translator System). I assume Spokane WA got TSPS for Operator Services before divestiture in 1984 though.
With only a cord-board for toll services, you did NOT have 1+ coin, you did NOT have 0+ dialing of any kind, and ONLY ESS offices (from non-coin) could have SOME form of 011+ IDDD, sent-paid non-coin traffic only (i.e.., no 01+ IDDD special-billing customer dialed calls). I remember trying to dial home to my parents in New Orleans collect for several days after the volcano blew its stack. I would simply keep dialing '0' from a payphone until an operator would finally answer.
They were trying to be helpful and polite, but they couldn't answer all the call requests immediately. And the 4A crossbar toll machine and associated card-translator must have been overwhelmed. Even when I could get an operator on the line to talk to to place a collect call back to New Orleans to tell them that I was safe, all the operator might get was re-order (fast busy) or some kind of ccts busy recording.
And all operators in their frustration were actually saying: MY BOARD IS LIT UP LIKE A CHRISTMAS TREE! That is really how manual toll cord boards were like whenever there is a disaster or other types of high call volume.
mjc markjcuccia at yahoo dot com