As the “race to 5G” continues, U.S. carriers Verizon and Sprint have disclosed small but important new details of their upcoming network rollout plans, fleshing out the 5G services they expect to offer in 2019. Verizon is now actively planning for a launch of mobile 5G, and Sprint hopes to bolster its 2.5GHz 5G network with ultra-high-frequency millimeter wave spectrum — assuming T-Mobile doesn’t acquire it first.

Having already announced and recently reconfirmed plans to offer “fixed 5G” home broadband service across three to five U.S. cities in 2018, Verizon CEO Lowell McAdam told the Seattle Times that its mobile 5G service will be “only about six months behind” the fixed launch. Assuming Verizon launches fixed 5G any time after June, that would place the mobile 5G launch in 2019.

A fall or later Verizon fixed 5G launch appears to be most likely, as the carrier hasn’t announced most of the cities it will service and the 5G broadband hardware is just beginning to appear in public. Three days ago, the FCC approved the first Samsung 5G home router, which Verizon is expected to use in its fixed 5G launch. But Samsung requested confidentiality until October 27 for the device’s manual, suggesting that the product’s debut in homes isn’t imminent.

Launching mobile 5G in 2019 would place Verizon behind rival AT&T, which is planning a mobile 5G rollout in a dozen cities later this year, but around the same time T-Mobile and Sprint plan to start offering mobile 5G services. All of the carriers are constrained by their ability to offer 5G smartphones, which are not expected to be available in large numbers until 2019. Regardless, AT&T plans to get a head start on the mobile 5G market by offering portable hotspots in 2018.

Sprint may not be an independent company when its 5G network launches, but that isn’t stopping the company from planning for the possibility that regulators will scuttle its acquisition by T-Mobile. A FierceWireless report today notes that Sprint is actively interested in pursuing high-capacity, short-distance millimeter wave spectrum for its 5G network. The 24GHz to 28GHz spectrum would bolster Sprint’s currently 2.5GHz-exclusive coverage, assisting in urban and other areas with high device density.

Millimeter wave spectrum is considered important enough to 5G that Verizon and AT&T each purchased companies with substantial millimeter wave holdings to avoid depending on government auctions. Sprint and T-Mobile previously held off on ultra high-frequency investments, saving money on both the government-leased spectrum and its required small cell hardware. But the FCC now plans two millimeter wave auctions for later this year, enabling more players to build 5G devices with high bandwidth capabilities.

However, it’s unclear whether Sprint will actually bid in the FCC’s auctions. Sprint executives have not confirmed their participation, and separate reports indicate that T-Mobile may seek regulatory permission to enable the two companies to coordinate auction bids during the merger approval process. T-Mobile has previously expressed an interest in using millimeter wave in 5G, but said this week that the low- and mid-frequency spectrum held by a T-Mobile/Sprint combination would enable a massive rollout of both mobile and fixed 5G services next year.

Somewhat amusingly, Verizon’s McAdam also took the opportunity to dismiss the T-Mobile/Sprint merger, telling the Seattle Times that “we don’t have a point of view on whether it goes through or it doesn’t. We frankly don’t care.” Responding to a suggestion by T-Mobile that the merger would help push the entire cellular industry forward on 5G, McAdam said that Verizon has made its moves without waiting on competitors — a prospect he called “frankly silly.” Verizon is the nation’s leading carrier with an estimated 160 million customers, and it has committed to being the nation’s first 5G provider, even if that means updating its initial 5G hardware after international standards are finalized.