It seems like the article may be intentionally vague on this point, but I can't tell if already-grandfathered unlimited 4G customers are going to have it yanked

It seems like the article may be intentionally vague on this point, but I can't tell if already-grandfathered unlimited 4G customers are going to have it yanked this summer (which I guess would let them out of their contracts on their subsidized phones scott free), or if they simply won't be able to renew the unlimited part once their contract is up.