Orbi RBS750 has no WiFi signal

Hi gang - I bought an Orbi AX4200 RBR750 with 1 RBS750 satellite almost a year ago. My hardware warranty expires soon, so I'm hoping to get an answer quickly in case I actually have hardware issues.

RBR firmware is at v4.6.3.16, and I'm assuming the RBS is at the same level but can't find where to confirm that.

I have the RBR set up on the main floor and the RBS in my home office upstairs. I have my laptop and a wireless sensor network base station connected via CAT 6 cable to the satellite. With 500 mbps fiber to the house, that gives me absolutely stellar performance from my laptop. I also enjoyed dropout-free solid WiFi for months with no issues. However...

Recently the WiFi performance has been spotty so I used the WiFi Analytics function in the Orbi app to check coverage. I was surprised to find absolutely zero radio signal from the satellite (-75dbm and no increase as I got closer). Obviously the backhaul radio is working fine, as the devices I have connected directly to the satellite are working great -- but I got no WiFi signal.

Um, as I was typing this post I watched the signal strength jump from -75dbm to -25 dbm. That pretty much explains the spotty WiFi in my house, but what's going on with the RBS750?

I have tried restarting the RBS several times, once I left it off for a day. I have not tried updating firmware yet. Is this something that could be fixed with a firmware upgrade, or do I need to pay for Netgear support to report a hardware issue?

Thanks for any feedback!!