I've been thinking about the hand/sunflower stamps (assuming they aren't fictional). While we can guess all we want about them being two groups of classification, they could just be some other internal designation to keep the paperwork pages together (like Copy 1 and Copy 2). I remember wondering about strange things in the ADCs and then finding out that they had innocuous meanings, so ...

If not an "innocuous" designation, then one guess is that sunflower might code for more passive (e. g. vegetable) and hand might code for active (e. g. animal). While armed robbery might seem kind of "active", it includes picking someone's pocket while you happened to be carrying a weapon (e.g. extra-large toe-nail clippers - lol) (versus putting a gun to their head and grabbing money off them). They may have considered you less "active" than other inmates especially if it was your first time sentenced to more than one year (6 months with good time).