From the email I just received:
Ride free this weekend
Whether it’s a trip to the local pub, a ride home from the shopping centre or you're planning night on the town, trips in Bradford, Dewsbury and Huddersfield this weekend are free up to £10.
From Friday, September 2, at 5pm through Sunday, September 4, anyone who requests a ride in Bradford, Dewsbury and Huddersfield will get up to £10 off up to 10 trips—whether you're new to Uber or an existing Uber user!
That means that an uberX trip from Mirfield Train Station to the John Smith's Stadium (ordinarily around £7 to £10) or a trip from Shipley to The Broadway Bradford (ordinarily around £5 to £8) could be completely free. It’s that simple