The P3 toll road from Mustang to Seguin has always been 85mph.
Not according to NPR in 2013: https://www.npr.org/2013/12/17/248757580/even-an-85-mph-highway-cant-fix-austins-traffic-tangle
From the Article: "Texas Highway 130, a new Austin bypass toll road, is so far east of the city that it sees little traffic. The state recently raised the speed limit there to 85 mph in hopes of boosting its use."