Im very much scared of this. It doesnt help much when I have already been through this scenario.
2 years ago when the Iphone 3g came out, I had a grandfathered text messaging plan with ATT that was 50 text a month for 2 bucks a month. My wife and I dont text that much and it met our needs and was cheaper then paying the horrendous charges they charge for not having a plan. We bought my wife the 3g, and they asked if we wanted to upgrade text plans or anything. We said no and they said ok.
Fast forward a month when I get my bill. I had no text plan on her line. It had been removed. And was removed the day we got her Iphone. I screamed and hollered about losing the plan and wanting it back. I went up the chain to a manager, and their manager. I couldnt get it added back because it was no longer in the system. You see once a grandfathered plan is "grandfathered" they remove it out of the system that no matter what no one can add it back. Sure I got a new text plan, 200 texts for 5 bux a month, and several months of credit...but I still lost the plan. Simply due to the fact they cant add it back.
Now the unlimited data plan has been "grandfathered". If they remove it, even by "accident" they wont be able to put it back on as they have removed it from the system. I will be ordering my wifes 4g phone through Apple.com in hopes that I avoid this mess. However I have another monkey wrench. That same rep who botched this up screwed up our upgrade plans at the time. They used my upgrade instead of hers to upgrade her 3g. She bought me a 3gs in december for Christmas, and used her upgrade to upgrade mine. So now I have to use my upgrade to upgrade her phone since her 3g is on its last legs. I fear of problems but I will be avoiding any humans at att like the plague. I wish I had an apple store here...