If you’re like us, keeping a smart phone for two years really isn’t an option. After about 6 months of ownership the honeymoon is over; after 9 months you begin to obsess over a few battle scars your phone has acquired, and by month 12 you are actively seeking your phone’s demise so you have an excuse to buy the latest and greatest. Starting immediately, T-Mobile will be offering post-paid smartphone customers on a two year contract — or feature phone owners looking to upgrade to a smartphone — two tiers of upgrade pricing… as long as you are willing to renew your two year deal. The move is aimed at curbing the number of customers jumping from T-Mobile to other networks, specifically AT&T and Verizon Wireless. Customers will be eligible for a “tier 1″ discount if they have had their phone for 1-11 months, are currently in a two year contract, and have an individual voice plan that is $29.99 or higher — $49.99 or higher for family plans — and are upgrading to, or buying a new smartphone. Customers qualify for “tier 2″ pricing when they are in a two year contract, have an individual voice plan that is $29.99 or higher — $49.99 or higher for family plans — are between months 12-21 of their two year contract, and are upgrading to, or buying a new, smartphone. The exact discount pricing hasn’t been made available yet, but TmoNews speculates that a myTouch 3G, which retails for $400, would cost those that qualify for the “tier 2″ pricing around $240.