Here are some larger image sizes of the Shoal Creek Walk renderings. It's definitely 24 floors.
That's the roof line of The Monarch to the far left. This rendering makes Shoal Creek Walk appear roughly the same height as The Monarch. The Monarch is 323 feet tall.
Spring is 427 feet tall. So Shoal Creek Walk is shorter than that, but well over 200 feet since Austin City Lofts, (to the right of the red triangle), is 180 feet tall. I would estimate it's between 300 to 320 feet tall.