I have some July flights and Dec flights that have each had at 3 rounds of flight number changes in the past month, with no other changing details

every time it’s the same -

• Saturday morning flight disappears and I lose my seats
• no routes show up at all if I search for a new booking
• Saturday Evening I can search for the routes on DL.com and see they exist with exact same operator, time and route - but new flight numbers
• but I can’t yet change my flights on app or on web to get the new one
• I can text in to get them to fix it
• or I once waited for them to process on Monday but seats were gone

any way I can self serve fix or anyone know why they are updating the same routes so much for flight numbers only?

Numbers fir most part are randomly assigned except for 300 and below.

As changes are made numbers get reassigned. It also issue due to limits of flight numbers. This is a bigger issue nowadays than in past years, due to # of flights.

Schedule change starts on Saturday, but depending on size of load, can run into late Sunday.

FYI, I've recently had Schedule Change Saturday issues not resolve until Wednesday.

In many cases where the flight is a regional, flight number changes reflect a change in regional carrier. If that’s the case, congrats, you have free rein to switch to different flights at no fare difference (due to change in operating carrier).

OP, I've had the same over the past few weeks. About 2-3 weeks ago I woke up on Saturday to see a flight schedule change. Couldn't do anything with the reservation in "My Trips". Did a dummy booking and could see there was a flight at the same time with a new flight number. Seat map showed the seats I had as occupied so I didn't worry too much. Took until Sunday morning before everything cleared up and I had the same seats and flight time. Only change was the flight # change (DL Connection flight, same regional operator).

Same thing happened this weekend though at first I was more nervous as when I tried a dummy booking, there was no flight showing at that time (~1:00 PM), only a 6:30 PM flight which wasn't going to work connecting to my international connection. A little while later though my 1:00 flight was showing as bookable again, just under a new flight number, again (same DL Connection Carrier).

One on the longest SCS specifically for connection carrier changes. The website wouldn't allow me to open a regional-only itinerary in MyTrips until early this (Monday) morning. Dummy booking showed my seats filled, so wasn't going to worry or call until later this week.