Finally...some news on the ECC site:
New planned downtown tower could be Austin’s second-tallest building
The article describes the tower as "Austin's second tallest..." However, that may be incorrect. At 50 stories it would be the second tallest by number of floors. But, a 50-story tower "could" easily rise higher than the Austonian in true height.
The article did mention the tower would be "50 stories and possibly higher."
“We want the building to have a lively presence on the skyline,” Brett Rhode said (Rhode
artners Architects). “This will not be another generic tower.”