Don't Install iOS 10.2.1 If You're Traveling
If you're about to hit the road on a trip for the holidays or if you're in the middle of a trip, we strongly recommend putting off iOS 10.2.1 until you're back home.
Over the years, we've talked to a number of people stranded with a malfunctioning device because they updated to a new version of iOS right before leaving or during the trip itself. The last thing you want is for apps and services to breakdown when you're in a different city.
If you are traveling away from your comfort zone and your backups, it's a good idea to wait to do this upgrade until you get back to your base of operations. If that's the hotel, so be it.
It's probably not worth putting a personal trip, a business meeting or an important business trip in jeopardy to get iOS 10.2.1 on your phone or tablet.
Wait until you have some downtime and then install iOS 10.2.1 if you need it.