$449 question and plan

[ekim524778]

ok heres the deal. i have a pre order at RS for the Evo. Currently Im on the 49.99 SERO plan, and i know i have to change my plan... Also im not eligible for an upgrade until Sept 15 2010. I dont have a problem with paying retail for the phone. My questions is what route should i take as far as plan and or any discounts and when should i do the changes.? I heard about the 10/24 option and the $70 credit for renewing contract, etc.
Im eligible to be a S Premium customer, just havent placed the called yet. Im thinking about getting $99 plan, and try to get one of those corporate discounts , i know of the 25% off one, may try to get more info on the 27% off one (someone pm me the company that gets 27% off) .
When i change my plan will they extend my contract? if they do that i may as well terminate my current contract and pay the term fee and just get evo for 199$.... cause i will still be a premium customer and can upgrade annually...
Just want some thoughts on what routes i should take.
thanks