Have backup plans for in case something fails. You use a libre, so of course you're going to want to pack extra sensors and adhesives. During my last trip, my Dexcom transmitter failed (the only thing I didn't bring an extra of since you only change it once every 90 days), so I had to go back to the classic finger prick testing method. I brought my meter and a 50-count of strips with me, so I was good until a new transmitter was shipped, but if I didn't pack it I would have needed to go somewhere like
Walmart or a pharmacy and buy supplies there.
I had a similar experience in October, 2020. My Dexcom Transmitter failed a couple of days into the trip. Of course, that was the one thing I didn't pack, since I wasn't due for a replacement. Dexcom was understanding, and sent out a replacement transmitter right away, but since it was a weekend, I was stuck waiting until Monday (at the earliest). I went ahead and took a Lyft to a nearby Walgreen's, which had transmitters in stock, and had my prescription refilled.
Now I always pack a backup transmitter.
When I get up to the TSA desk, I let them know that I have a medical device that cannot go through the scanners and that I have medical supplies in my bag. What ends up happening is that usually I go through the metal detector instead of the full-body scanner and get a pat-down while my bags go through regular scanning and often a hand-search too.
TSA Pre-check has been great for this. Though, with my new tandem pump, the all metal body sets off the metal detector. In order to avoid going back to the days of getting a pat-down for every flight (I fly often for work), I now do the following: 1) I detach my pump right before going through the metal detector 2) Inform the TSA agent that I have a medical device which can't go through the XRays and will set off the metal detector. They will take the pump from me, usually, and do a residue test on the pump itself, while I go through the metal detector. I make sure to keep the agent w/ my pump in LOS, and it normally takes less than a minute or two before I get my pump back to re attach, and I'm on my way.
My other general advise for Disney as an insulin dependent diabetic is: 1) Have some ways to keep yourself cool in the heat and sun. I always have a personal fan I can take out of my pocket, and those
cooling towels they sell are great. Your worst enemy is dehydration. 2) If you're not on an insulin pump that adapts to your glucose levels, or you're not on an insulin pump at all, then have a frank discussion with your endo before you travel. Talk about options to reduce insulin dosage while you're on your trip. You might not need it, but I find that I tend to use as little as 50% of my normal insulin for a day at the park. 3) For travelling companions of the diabetic, be understanding. When I go to Disney, my glucose numbers can get into a roller-coaster of ups and downs on some days, and it is exhausting and can throw a wrench into some of the park plans. The worst part of it is feeling that I'm disappointing my kids because we're not making it to a ride / show in time, but having people that understand the challenges goes a long way to mitigate that.