Hi! I did a similar thing, flying from DC to California a few years go. It was originally a vacation but turned into a move about 2 months prior, so we flew to my sister’s house in NorCal and then a week later drove down to SoCal where we currently live. My bun has always been very chill for a rabbit so it wasn’t too stressful for him but here are some tips and things I learned!
-if possible, take her on a bus ride or two to see how she deals with it, since a bus is more similar to a plane than a car where you can control noise and movement more. give her her favorite greens and treats to try to help her calm down.
-for the flight, put down a puppy pad in your rabbit’s carrier along with like a large handful of hay (and bring an extra plastic baggie of hay in case you need more). i wouldn’t put too much because your bunny probably won’t eat a lot on the trip because she’ll be stressed out, but buns do eat during take off and landing–somehow they know that that’ll help with the pressure change in their ears, it’s wild
-definitely try to start out your travel day with the same routine and feed her as normal. pack some fresh greens and treats if you can and try to feed those while you’re at the airport and if you have a layover, since greens are more enticing than hay or pellets. pack some critical care and a syringe just in case she doesn’t resume eating when you get to your final destination, although she may surprise you.
-i would recommend packing a canvas playpen like this one and setting her up in there for your entire time at your air bnb and the first week or two at your long term place (with supervised playtime outside of it, of course). too much space too quickly is definitely stressful, especially in a new environment, and if she’s used to the playpen when you move, it’ll be like the same space when you set it up in the longterm apartment.
-one of the flights i was on told me that i had to put him under the seat during take off and landing unless he was an emotional support animal but my second flight didn’t care if i kept him on my lap. i honestly think he was calmer when he was under the seat because he didn’t feel my movement and it was darker and probably quieter so just know that whatever you choose to or need to do is going to be okay for your bunny.
overall i was really surprised by how well my bunny did, considering he hadn’t been in a kennel for more than an hour maybe before that. your bun is going to be fine, i think in a lot of ways the build up is more stressful for us than the actual event is for them, but if you have any other questions i’d be happy to give my input!