Today I decided to go spotting at KSAT after my baseball tournament finished. As I was pulling up a United Max9 departed from KSAT headed for KDEN. I quickly pulled out my phone (iPhone 11 pro) and got a few photos. Here are the best ones.
The flight number is UAL759. The tail number is N37504. Here is a screenshot from planefinder.com.
I hope to see this the next time it departs.