"Seven 4G LTE devices with AWS-capability are being sold by Verizon Wireless today. They include two Samsung 10-inch tablets, two jetpacks, a USB, the Samsung Galaxy S4 and the Nokia 928 Lumia.

Because, as this article says and the chart shows, the lower half (the half used for phone-to-tower) is completely different. It lines up with DCS, but not UMTS 2100.

Washington — Verizon, AT&T and Dish came away from the FCC’s AWS-3 (Advanced Wireless Services 3) spectrum auctions as the biggest winners followed by T-Mobile. Sprint didn’t bid for the high-band ...

But why is the AWS spectrum band important for the rollout of LTE network technology in the United States? To date, most noise on the LTE front has been in the 700 MHz band.

No current phones (as of October 2006) are capable of operating in the AWS band. ... The chart above also shows why current UMTS 2100 phones aren't compatible with the AWS band. UMTS 2100 phones ...

And AT&T's LTE devices support both 700 MHz and AWS bands for LTE. (An AT&T representative declined to discuss whether the carrier has launched any commercial AWS LTE markets.) ...