Depends on whether the character is blocking more or less light in their new position.

The shadow contracts until it gets more than halfway between the light source and the ground. Then it expands until it hides the light source and subsequently covers everything.

To be more specific, I'm talking only about the sun. I know a shadow would expand under a lamppost, but the sun has different rules if I'm correct.

The shadow contracts until it gets more than halfway between the light source and the ground. Then it expands until it hides the light source and subsequently covers everything.

Makes sense, but so does Captain Marvel's response. I get it does depend on the object's location relative to the sun?

It depends on the size of the object as well as its location relative to the light source. If the light source is the sun, then the shadow would contract, unless you had a large enough object (eg/ the moon) that could block the sun's light.

Okay, so I was right -- it sounds like that blob shadow prefab was intended for lampposts and the like.

Thanks to everyone who replied!

P.S. The sun's out today. Amazing!