It's a mess.
When laid out the UHF TV band was 420MHz wide. It's now 138 or less. The TV band starts at 470MHz but as we know up to 520MHz is reserved in some markets for other services.
Yep, TV now ends at channel 36, 608MHz. Channel 37 is and has long been reserved for radio astronomy. (There actually were a few construction permits for 37 over the decades but they never went on the air) My opinion only, the only way TV is going to get those channels back is if we clear more of the upper ones making the 600MHz band wider, down to 560 or some such. They may, but I can't see mobile networks wanting to add yet another 50MHz to their networks down that low. I would suspect if they auctioned off 560 to 608 some of the proceeds could go to TV stations to move to 470 to 520.
Phase 7 of 10 in the TV repack is coming up in January.
The NTIA is hoping to clear 3.45 to 3.55 GHz for mobile broadband. This will severely disrupt the 3.3 to 3.5 GHz amateur band. The FCC (Docket 19-348) is considering eliminating that entire amateur band and also considering if feds and commercial wireless can co-exist from 3.1 to 3.55 GHz. They want to clear 3.3 to 3.55 and perhaps clear 3.1 to 3.3. In all opening 250Mhz of "flexible" spectrum. Plus, the FCC is looking at taking 280MHz from C-band satellite range of 3.7 to 4.2 GHz. Broadcasters using the spectrum are happy, willing to sell. Companies operating the satellites are furious.
The DOD operates high power radar from 2.9-3.65GHz. Clearing Fed users might be difficult. If federal incumbent users vacate the NTIA could turn over their portions of 3GHz. Funny, the FCC & NTIA agreed on a new Citizens Band of 3.55-3.7.
This could clear 3.1 to 4.2 GHz, with some guard bands and possibly a few remaining C-Band satellite channels. There's also consideration to repurpose some of 5.9GHz spectrum.
At the end of it all I picture mobile broadband networks using 560-758, 775-788, 817-851, 862-896 MHz, 1.85-1.9, 2.305-2.32, 2.345-2.36, 3.1 to 4.2 GHz, maybe more?