I purchased an iPhone in August 2009, and currently have an upgrade eligibility of 1/15/2011 (17 months after purchase). I missed the instant-upgrade eligibility cutoff by two weeks. I am wondering, however, if increasing my monthly fee would result in an immediate upgrade. Currently the monthly bill for my line is $90 ($60/mo 700 minute family plan and $30/mo unlimited data). If I were to add, say, Messaging 1500 to my plan, that would put my monthly plan at $105. This should move my eligibility up to 12 months after purchase, putting me in the instant eligibility window. Anyone have any idea whether this will work? Do such eligibility changes take effect immediately? After the first billing period? Or after some other period of time?