Booked a ticket directly online with KL. 074-stock, 2 KL segements, 4 DL segments, KL flight numbers on all six.

Only minor issue with the reservation was that three of the four seatmaps for the DL segments were "view only" on delta.com (on the Delta app I couldn't even view the seatmaps, the screen froze). The fourth I could change as normal. I was happy with the automatic seat allocation on two of the other flights, called Delta about the last one. They changed it as per my request. Since the change did not show up online, I called the FB Plat line to get it fixed. That worked. Neither Delta nor the Plat line could tell my why I couldn't select seats myself. I still can't.

Then today I got an e-mail from something called KLM Sales & Service Center, asking me to call them within 24 hours about this reservation. Before doing so, I checked both the KL and DL sites. The only thing I could find was that on the DL site one of the DL segments was marked with "Schedule Change" and a green check mark, presumably meaning that the change did not affect onward connections. Strange thing was, I could not figure out what had changed: departure airport & time, arrival airport & time, aircraft type, seat number, everything exactly the same as in the original booking.

To be on the safe side, I gave the Plat line a call. The agent turned the booking inside out and upside down, but could not figure out what the issue was, if any. She finally decided that it was all because of an equipment change resulting in a seat change. But the seat change she saw was the one I had made over the phone some weeks ago, and there was no equipment change. Instead of disabusing her, I thanked her politely and ended the call.

I then went back and checked the booking again on both websites. What I finally found was that the "schedule change" DL segment had gone from a KL flight number to a DL flight number on Delta.com, whereas the same flight had changed from a KL flight number to an AF (!!!) flight number on KLM.com. All other five segments showed the original KL flight numbers on both sites.

Duh? Huh?

I assume the e-mail was auto-generated, and I really like getting those when there's an issue that has to be dealt with, e.g. a material schedule change that requires my approval, or a (partial) rebooking, etc. But when they have only changed the flight numbers (for reasons that are no doubt very valid, but a complete mystery to me) I would rather they left me alone instead of demanding I phone them within 24 hours.

Johan