Ha! It's amusing how companies can give "promotions" which are essentially "here's more work... for marginally better pay..."
Anyhow, for the kind of jobs you're after post-MBA (i.e. it's more Big4 and less McKinsey/Bain/BCG territory), you don't need to go to a top 8 or even a top 16 school. Not sure where you're based or where you want to be based geographically, but I'd focus on maybe a handful of the top 16 like Ross, Duke, Darden, Haas, UCLA, NYU, Cornell, Yale (choose maybe 2 or 3), as well as a few schools outside the top 16 like Georgetown, Texas, USC, UNC, Tepper, Emory, and so forth (choose 2 or 3). These range of schools should still get you the kinds of jobs you're looking for.
Alternatively, you can always do a part-time or exec MBA at your age -- especially if the money is a big concern (i.e. you're married, have kids, etc).
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