More than six months after Citymapper launched its own officially licensed bus route in East London, the transportation app is is now launching a new endeavor: becoming a private taxi operator, according to the Financial Times. London’s transportation authority, Transport for London (TfL), confirmed to the outlet earlier today that it has granted Citymapper a license to operate a taxi service, though there are no details about the forthcoming service.

Full details about the next phase of Citymapper’s London transportation experiment — like scale of the service, number of cars, or area of operation — have not yet been made public. They’re likely being saved for a third blog post. Financial Times says it only got the heads up when it noticed an errant, since-deleted post about the news of the taxi service on the TfL website. Citymapper previously partnered with Gett for carpooled rides in black cabs along a fixed route.

The Citymapper team has been operating the overnight bus route in London since early last fall, and it updated the progress in two blog posts on Medium within the last 48 hours. One, called “Good Bus (Part 1/3)”, describes some of the things that the Citymapper team thinks it did right in trialing its own late night bus route. The team touts how its bus service offered smart features like contactless payments, open seat tracking, smart displays, and USB chargers. The bus was also a social media hit, Citymapper says, with its pop music playlists and features like displaying rider-specific emoji on the screens to let people know when they arrived at their stop.

In a second post, “Bad Bus (Part 2/3),” the Citymapper team says it has also spent much time running into regulatory walls. For example, one weekend into running the bus, Citymapper decided it wanted to change the route based on early rider data. “We had to wait weeks before our change was accepted,” the team writes. “Its [sic] hard to innovate and iterate on such timelines.”

A taxi service should “go wherever you want, however you want, how often you want,” Citymapper says

Citymapper’s buses don’t really deal with more than two dozen riders at a time. And since TfL allows up to eight passengers in for-hire vehicles, Citymapper says it sees the opportunity to develop a service that can “go wherever you want, however you want, how often you want.”

“As a result, a private hire vehicle can respond to demand, a bus cannot,” the team writes. “That makes it hard for a bus, even a smart green minibus, to be part of the ‘demand-responsive’ future.”

Operating its own taxi service would be a whole new challenge for Citymapper. TfL has closely monitored for-hire private vehicle services after spending years locked in a battle with Uber over its aggressive practices. (For example, the TfL just passed new driver regulations last week.) That means Citymapper will have a completely new set of opportunities — and potential roadblocks — ahead as it shifts from buses to taxis.

Correction: Citymapper has shared that it isn’t shutting down bus service in London, despite the original Financial Times report. This story has been updated to reflect this.