Blend direction along the path, how to change??

A blend, like from square to circle.

Then a path, which is kind of a circle. To be simple, let's make a circle.

Select blend, set new path, point circle.

Blend will go along the circle, right?

But, if You want it to go to an other direction with the blend?

How to change it?

I realized, moving 1st object in blend, over "midpoint", will change blend from CW to CCW, depending from which side to go over.

This is basically what I want, but how to control the place of a "midpoint"?? (If that's the way to do it.)