from what i'v found, you cannot change feed override during an arc. if you do, it will still register that you hit the < key, but not show up on screen until the next step. if you hit it more than once it will jump 2x or more. same deal when on a straight line, it just shows up on the screen immediately and waits til next step to change speed. interesting how v3.1 didnt have this problem. also iv made it a habit never to jog z when i hit esc during an operation, because there it will not register that z moved, and will screw up your piece.