There is no bucket. There is affirmative action. If you can prove you're a part of a group for which affirmative action has been granted they'll give you a certificate saying you're part of that group. This is in no way tying you to that group. It's just a scheme to give affirmative action.

This is like saying America's racial quotas (or former ones) put you in a 'bucket'. Caste is essentially race / genetics. You are not bucketed, it is simply a reality of your ancestry. Of course you can't change it.. you cannot change your genetics. This is a ridiculous goal post.