Regarding A.T.Kearney, they hire freshly minted MBA at associate position, this is in their standard process. When you add experience to this, they will eventually considere your situation indivivudally and this would very much depend on your experience (type of industry, nbre of years of experienced). What they can offer in the end is either an associate position with fast track perspective (you'll have higher salary, and perspective to be manager in short term), or hire you directly at Manager grade if they think you can do the job. Depending on your experience this latter option can be challenging, especially if this is your first experience in a consulting like industry.
Don't hesitate to reach me if you have more specific questions. If you detail a bit more your experienced I should be able to help appreciate mor specifically what they could offer.