With the new update Samsung Band Test1 brings up "NETWORK" menu(?). I can get into the Band Selection by clicking the menu button in the top left. I have never used Band Selection menu before but that is what it says in the top center.
I saw there were 7 different options I just figured I would let you know which seemed to work for me. No 5G in my area so I can't really test that part of the beta.
Well... They haven't been back to finish the tower. It's still looks the same today as it does when I took those pictures. According to someone from Reddit, which I shall take with a grain of salt, the crew made various safety violations on that tower and that they were probably kicked out of the market. So maybe that's why it remains unfinished? It does seem weird that they just up and left leaving wires just hanging.
This is the photo I posted in /r/CellTowers
Side note: I noticed Band 5 LTE going away in some areas. A tower in Bittinger, MD previously had Band 5 LTE and now it no longer does. It still has band 2 and 17 and no aggregation, at least not with my phone. I think it used CA with my ZTE MF288 modem. The Band 2 has 15 MHz bandwidth and hits 80 Mbps no problem.
I finally got around to an actual test, in the same location, first with 5G enabled, 7.42 D/L and 0.07 U/l 45ms ping. Then just a couple minutes later, after the reboot from switching to LTE/CDMA mode, 33.8 D/L and 6.31 U/L with a similar 44ms ping. This was pretty far from the tower, but I've noticed similar differences in many locations. Also, I have not had a verified connection to n71 in about 5 days, looking in the *#0011# screen, while a speedtest, or other data in use.