I used to enjoy flying Jetblue; their planes were upgraded and fares competitive compared with United and Delta.
However, I had booked four nonstop domestic flights through them in winter/spring 2022, and for all four itineraries my flying partners and I received e-mails a month to 6 weeks out that our booked flight had been cancelled. Our options were either to change to different flights with Jetblue (without fees of course, since it was the airline's fault for canceling), or cancel our flights altogether for a refund (and presumably rebook with a different airline).
Canceling didn't make sense at the point we were notified since the other airlines' fares for similar flight dates/times/cities had already shot up to at least twice as expensive, and the rest of our trips (hotels, rental cars, etc.) were already booked so flexibility was limited. In at least 3 of the 4 cases, our best alternative option in rebooking with Jetblue was a one-stop flight, which was of course worse than what we originally booked but getting a discount on the original fare was not an option. For the fourth flight a nonstop was still available, but the time was drastically shifted from early morning to early afternoon, limiting our time at our first stop.
Maybe it was a factor of COVID chaos, but this 'change trapping' that technically modified the service we had originally paid for didn't sit right with me, and since then I've generally avoided booking flights through Jetblue (except for one 2023 domestic fare that was nearly impossible to pass up). The worst a different airline had done was move a booked flight up by 2 hours (American) or 1 hour (Southwest).
