You're right, "no seats on Wednesday" is general revenue management.

If there's any sense to this, POS has to funnel *sale* of segments to persons buying at a high-priced place, so a person attempting to buy from a low-priced place won't see availability.

Once the ticket is sold, there's presumably little reason for the airline to care about subsequent reservation changes because for point to point tickets the passenger must have paid the higher fare to have gotten the ticket in the first place - open-booking from a place where the seat wasn't available being presumably microscopically rare.

That leaves multisegment trips. Would the airlines have bothered to add that to the programmer's specification? Seems unlikely anyone would have thought of it, or paid extra for it. (Programmers, on staff or on contract, do NOTHING for cheap).

But if they did, no xONE issued anywhere would ever be allowed to fly a POS-controlled seat (until the restriction was lifted). The per-segment revenue gleaned from an xONE ticket is not knowable until the trip is completed, and even booked from a high-priced point is likely to be pathetically small compared to any point-to-point A/D ticket.

So I think we have to be careful blaming availability on POS - it probably fogs the real issues.