complicated mask_attack or brute force?

[drsnooker]

You could run a script that contains 12 different attacks.
-a 3 ?d?d?d?d?d?d?d?d?d?d?d?u
-a 3 ?d?d?d?d?d?d?d?d?d?d?u?d
-a 3 ?d?d?d?d?d?d?d?d?d?u?d?d
-a 3 ?d?d?d?d?d?d?d?d?u?d?d?d

etc
eventually you'll hit the right position. Could re-sort the attacks to go middle out, if you think the odds of finding the upper case letter are in the middle rather than the extremes