Not only will you have to upgrade your DVR…but more than likely you will have to upgrade your streaming devices - as most do not support AC4 audio. I have 3 Roku Ultras (2017-2019 models), 2 Streaming Stick Plus and a FireTV Cube, none of them support AC4 audio.
Currently with my HDHomerun tuner, I can watch (with sound) only on my XBox One and my computer.
But even then, when your city is “live”, it may only be in test mode (like Austin, TX is - with one channel showing on TV now), and it will probably be the same HD broadcast (with AC4 audio). No 4K shows have been broadcast yet.
It will probably be 3-5 years before widespread adoption of ATSC 3.0. My HDhomerun is a “gadget” at this point, I only use it to view the signal qualities of stations, and do channel scans (it is quicker than doing it on the TVs). Currently, only the SiliconDust DVR system supports ATSC 3.0 broadcasts (Plex and others do not).
It is not “prime-time” as of yet. I am sure that Tablo is following what is going on - but to release something now will just create a firestorm of technical support issues…and not worthwhile to most users…