Here's the nine page approval from the FAA for the 847' height for 600 Guadalupe. The height was approved just two weeks ago. It mentions the 499' height limit then goes into FAA speak about the additional height allowed for this project. Maybe somebody can make some sense out of this.
EDIT: The height determination report for 600 Guadalupe didn't display for everyone using the link I previously posted. Click on the determination PDF in this link to see the report:
https://oeaaa.faa.gov/oeaaa/external...3862654&row=58