Sorry to hear about your troubles. It sounds like you've had a string of bad luck. You're right, your work environment is not optimal for smartphones. However there are some amazingly strong cases available now, that make them nearly indestructible.
Yes, there is a deadline by when you need to apply for insurance. Unfortunately, there's a lot of fraudulent activity in the cell phone business, and one of them is insurance fraud. Obviously you're not trying to do that, but the cell phone companies have had to put in these requirements in order to cut down on that activity. They all do it, so it's not just a T-Mobile thing. I don't think any of them are very good at calling out the deadline either.
T-Mobile's monthly and contract unlimited data plans, out of the box, comes with 2GB of 4G data. It switches to 2G data after that, but at least they don't cut you off like ATT and Verizon do. And of course, you can upgrade to 5GB or 10GB, should you find constantly go over 2GB.
