I've been T1 since 8 so all my travelling (max 2 months) has been done with T1. I agree with what
@In Response said.
I've only once been asked for a letter to prove I was diabetic for my supplies (Hong Kong?), and though I didn't have one I managed to convince them (eventually) using an Australian diabetes card, so it's probably worth having one if you are doing a long trip, specially as it should make it easier if you need medical care while overseas.
I've also (once in Dohar) had customs insist I put all my supplies through an x-ray machine, so if you have a libre or dexcom you may want to consider whether it's safe to go through that machine. Sensors may be awkward to buy overseas as the G7 is geolocked (have to download the software in the same country as you buy the sensors) and I'm not sure about the libre. Not necessarily a problem, just something to be aware of. I'd recommend taking lots of glucometer supplies, as you may find that the brand you use isn't available in the country you are in. (Though you could always buy a new glucometer). eg in New Zealand the only brand available in pharmacies is the caresens, because that is the one that is supplied on prescription to all diabetics.
I certainly wouldn't let T1 stop me from travelling, but you do need to be a little organised about managing your supplies. And a thumbs up for frio wallets from me too.
Would you like me or another mod to move your thread to the T1 or Ask a Question subforums? It will get better visibility there , because General Chat threads don't appear in the list of recent posts...