In January, a rescan of my TV picked up 8.8, duplicating the WFAA main channel. I saw from a Google search that 8.8 is on RF channel 30 in 720p, while 8.1 is on RF channel 8, still at 1080i. However BOTH were 720p then and have remained so.
Don't know why 720p is still popular. Back when HDTV had 26 inch low contrast LED screens, 42 inch plasma displays that were 480p, and 26 to 36 inch 16:9 720p CRTs, The higher frame rate did make sports look better. But today 720p on an 80 inch inch UHD (2160p) screen looks awful