The next band to be targeted is 3450 to 3550 MHz (of which, 3450 to 3500 MHz is allocated to Amateur Radio).
https://www.lightreading.com/spectrum-now-act-takes-aim-at-m...
https://www.lightreading.com/spectrum-now-act-takes-aim-at-m...
For those interested in how these frequencies are used by HAMs check out http://www.arednmesh.org. We hack routers and wifi point to point links to operate on those frequencies to build out large mesh networks.