We just had this happen with Delta, also. They cancelled ALL of our flights and rebooked us on flights that had a 9+ hr layover on the way there, and an 11 + hr layover on the way home. With two small kids and a disabled passenger, are you kidding?? So I had to rebook to a flight that leaves at 6 am (UGGGH!) and TOTALLY screws up our car rental, since we are now arriving 6 hrs early. Then coming home we are stuck with two connections instead of one, bumping our trip time from about 6 hrs as originally planned to over 12 hrs. We land at 10:30 pm. So I am guessing my kids will have to miss school the next day, and DH can't take another day off so he will be totally dead on his feet the next day. I am so ticked, but I am guessing that this is not the last time they will change things. I feel like I'm being penalized for planning early.
OK, I feel a little better now. Until the next change...