Verizon Communications Inc. is aiming for a spring 2018 launch for its new online TV service, which has been delayed at least twice as the telecommunications giant grapples with how to compete in the media world, according to people familiar with the matter.

While Verizon has shared its plans with TV networks, the timing of the web-based, live TV service’s introduction remains tentative and could be further postponed, said the people, who asked not to be identified discussing private information.

With its wireless business struggling to grow in a saturated market, Verizon is under pressure to expand in media to get more revenue from advertising. The company has settled on a strategy of delivering a sleeker version of cable programming over broadband, but getting the service to market has been a challenge. Staff shuffling, technology reboots and negotiations for streaming rights have bogged Verizon down, as has the news last month that media chief Marni Walden is stepping down.

Though competing services including Dish Network Corp.’s Sling TV, AT&T Inc.’s DirecTV Now, Google’s YouTube TV and Sony Corp.’s PlayStation Vue have gotten a head start, Verizon Chief Executive Officer Lowell McAdam hasn’t expressed concern about being late out of the gate.

Web-based TV is becoming ”a crowded field,” but it’s “absolutely critical” for Verizon to introduce its own platform, in part as an advertising vehicle for its AOL and Yahoo units, McAdam said at Bloomberg’s Sooner Than You Think conference last month. He added that the company would decide within six months whether to offer a stand-alone service or a partnership.

The delays in the project have created the impression of a strategic drift, according to people familiar with the matter. The phone giant has yet to finalize distribution agreements with top media companies, the people said.

Verizon’s track record in online video services has contributed to the ambiguity. Two years ago Verizon introduced Go90, a YouTube-esque collection of original ad-supported streaming shows. The company has never disclosed user numbers, but has acknowledged the audience has fallen short of expectations.

Verizon issued a Go90 mea culpa of sorts to Hollywood producers, filmmakers and studio executives earlier this year and overhauled the technology behind Go90 to make another attempt at luring viewers.

The departure of Walden, formerly a rising star at Verizon, suggests the project still faces challenges. The responsibility for fixing Go90 now falls to Tim Armstrong, the CEO of Oath, Verizon’s online media and advertising unit. His assignment is to integrate Oath’s ad placement technology with Verizon’s TV service.