A source familiar with Charter's wireless plans tells me that the company will be launching its long-awaited wireless phone service on June 30. That date could change if there's complications, but that's the date the company is aiming for, the source states. The source also indicates that the looming service will largely mirror the pricing Comcast has already embraced with its own Xfinity Mobile service. That's not particularly surprising, given the two companies have already struck a wireless partnership on research and handset negotiations.

Like Comcast's wireless service, the looming Charter Spectrum service will lean heavily on the Verizon Wireless network for cellular backup.

Also like Comcast's wireless service, Charter's service, to be creatively named "Spectrum Mobile," will offer users unlimited data for $45 per month--provided you also at least subscribe to traditional Charter fixed-line broadband service.

The "unlimited" data option will include 20 gigabytes of usage, at which point users will be throttled back for the remainder of their billing cycle (if it mirrors Comcast's own offerings here as well, that should be around 1.5 Mbps). The company will offer users the ability to sign up five lines of service without the per line access fees you see with other carriers.

Spectrum Mobile users will also have the option of paying by the gig, with Charter charging users $12 per each gigabyte consumed (again mirroring Comcast's Xfinity Wireless service).

This is just the first step toward Charter's broader wireless ambitions. In a recent filing, Charter makes it clear that the company is taking an "inside out" approach to wireless, by focusing heavily first on indoor connectivity (leaning largely on its existing WiFi hotspot footprint), then shoring up cellular tower support down the line.

The company has also been experimenting with various 5G wireless technologies like millimeter wave, and has even hinted at eventually offering a fixed wireless offering down the road.