Do you have big plans for this summer? Because T-Mobile apparently does.

The Un-carrier on Thursday revealed it is forging ahead with previously announced plans to light up its new 600 MHz airwaves by the end of this year. The timeline now calls for site testing to begin this summer, with commercial operations expected to follow later in 2017.

Back in April, T-Mobile CTO Neville Ray said the Un-carrier expects to have at least 10 MHz of 600 MHz spectrum clear and ready for deployment across an area covering more than 1 million square miles by the close of this year. Ray indicated the pace of T-Mobiles 600 MHz deployments would be “record-breaking.”

The announcement comes just a day after the FCC officially granted T-Mobile licenses for the spectrum it won in the auction. As detailed in the auction closing announcement, T-Mobile exited the proceedings with some 1,525 licenses that blanket the nation. A map from Mosaik shows the Un-carrier managed to snag 40 MHz of spectrum across broad swaths of the country, as well as at least 20 MHz in key markets like the New York City metro area and major West Coast metro areas around Seattle, Portland, San Francisco, Los Angeles, and San Diego.

“With the spectrum transfer complete, the real fun begins,” T-Mobile said in a release. “Despite the cries from skeptics, T-Mobile has already kicked off deployment activities and will see the first sites ready for testing this summer!”

T-Mobile declined to comment on where testing would begin, how many sites would be involved in the testing, and what exactly those tests would include. But the Un-carrier did say that those activities would set the stage for commercial deployments to coincide with the release of new 600 MHz-compatible smartphones from Samsung and “other manufacturers.” New handset reveals from Samsung and other major vendors like Apple traditionally occur in the fall.

In a Thursday note, Wells Fargo Senior Analyst Jennifer Fritzsche said T-Mobile's build announcement answers some questions that popped up amid buzz about a potential T-Mobile-Sprint merger. 

"If a S/TMUS merger is announced (reported by WSJ; neither co has commented) will TMUS pullback? We see this announcement as further evidence it will not retract in spending--even in the face of a merger," she concluded. "We note if a merger does come about, S's spectrum portfolio is lacking low band spectrum. Put another way, this is spectrum the combined entity would want (need?) to have."