My question though is, would that fee be levied EVERY time I added/re-added my iPad? If that's even possible?
In other words, I don't want to pay $10 for months I don't plan on using it with LTE, but if I know I'll be needing it I'd like to be able to add it back on and then drop it from the plan again. That's what I'm trying to figure out. AT&T wasn't clear about this.
Then you shouldn't go through AT&T Mobile Share plan. You should just have a pre-paid sim card in there, and pay for one month here at there as need it. You do that all from your iPad. AT&T will give you a new prepaid SIM card for free (if you instead have a Post Paid card - which links it into you main AT&T account, Mobile share etc). But you can't get the $10/month thing that way. It's more like $15 for 200mb or $300 for a couple gig (something like that).