Right now there is a police presence at a home in Antioch, a neighborhood in Nashville. The home owner is identified as a 63 yr old man with explosives experience and electrical knowledge. The RV is not visible in the photos of the home. It is visible in some Google images from 2019, and is definitely identical to the bomb carrier.
This is a good picture of the RV and a link to updates on the story.
I'm guessing that the make and model were identified and the police found a match in motor vehicle registrations, and the owner has some things that match up as a possible suspect.
The most concerning thing at the moment is that ALL services related to ATT in central TN, southern KY, and northern AL are out. This means phones, both cell and landlines, internet, credit card and ATM processing. 911 services are out for about 25 counties. Luckily all the counties have a battery of cell phones available, that apparently run off Verizon towers and do not use ATT services. They also have some sat phones.
All law enforcement in the area is manning their facilities 24/7, even in small towns, until communications are back up.
This building is not labelled as an ATT facility. It's a plain building with nothing on the front except a street number, a garage door, and a man door. So someone researched the location and it doesn't seem to be just a random building hit.