Apparent axis shifts as rotates

The upward movement get slow as the body goes up due to gravity(the upward speed is 0 at the top.)
Hence, apparent axis shifts to the part which has slower downward speed offsetting the upward speed ,that is more near to CG accordingly.

However, if rotation is faster, even if the whole body’s upward speed is the same, apparent axis looks more nearby CG for downward speed is faster.
For extreme example, if rotation is very fast, the body rotates as if it doesn’t move upward. Therfore, it looks rotating with the axis of CG.
As you can see in the following figure, the part which doesn’t move mostly is shifting according to the parabolic motion.

This story is related to Not Tip2 : Rotate with an axis of chest to get higher flip