Question - Walking behind the free-throw shooter, but outside the arch

[justacoach]

The restrictions that come into effect once the ball is 'at the disposal of the shooter' are as follows:
Players in marked lane spaces may not enter the lane until the ball touches the rim. Other players must remain behind the area delineated by the FT line extended and the 3 point arc. There is no provision that extends the painted 3 second lane. Where did you ever dream up this nugget???