Before you edit much further:
We want someone who has less than 12 years of MANAGEMENT EXPERIENCE. The reason is that if you haven't been coding for 12+ years...you probably are not "hands-on" enough
This arbitrary cutoff makes absolutely no sense. I'd like to see your quantification of skill drop off per year of management.
If what you are wanting is a hands-on technical manager, then you need to say so.
And it shouldn't matter if the person has been hands on for 5 years or 20.
But I feel I'm being a little too generous regarding your motives here.