It’s completely based off overall. I want to say the top 20% at each position or so are considered Type A, maybe the next 20% type B or something along those lines. These are based off the positions the system assigns them, not what you put them as (for instance, you can’t change a player to catcher to try and get a comp pick).
The actual overall line is roughly along these lines:
SP - 77/76 Comp A, 74/73 B
RP - 73/72 A, 68/69 B
C - 72/71 A, 68/67 B
SS/2B/CF/3B - 80/79 A, 76/75 B
1B/COF - I think 79/78 A, 75/74 B, but could be wrong