Rush Plus confusion at Metro is good business for Uber, according to the Taxicab Commission-taunting luxury cab service. Since Tuesday, the company has offered $5 off rides during Rush Plus hours. The deal ends today.

Refresher on Uber’s business model for those who missed the Taxicab Commission’s sting in January: Uber passengers order a cab through a smartphone app, then the company dispatches a cab for a hefty price—-The Atlantic estimates it costs 50 percent more than a regular cab ride.

“It’s gone really well,” Uber’s Rachel Holt says of the deal. She acknowledges that it’s hard to tell how much of the new business is being driven by Rush Plus and how much is being driven by other factors like the heat.

Who are these wealthy Washingtonians who take Uber to commute, instead of, say, party on New Year’s Eve? Who knows, but Holt says the service is used throughout the day. She declined to give trip figures.