Don't bother with OpenWrt on these devices. There just doesn't seem to be the appetite to get it to work well. Shame because they are small and dinky little devices. But stock firmware was better. If you have the $$$ then consider just buying a few RT3200's as wireless repeaters / router.
0:00 stock firmware connect to 192.168.0.254
0:00 2 solid green lights on
0:00 select 22.03.0-rc5 firmware and click upgrade, click yes
factory w/ hash cabdfa176a6e94890e146979ffec45f483c2f3245080e8cece86e9ebedd32a72
0:01 1 solid green, 1 flashing green
1:12 all lights off, rebooting message in web gui
2:10 1 green light flashing, IP on pc assigned 192.168.1.203 IP
2:50 1 green light flashing, successfully connect to LUCI on 192.168.1.1
OK but does 5Ghz radio work in a stable way and give reasonable performance? When I last tested it all went bad. But admittedly that was some time ago. I'd love to know if OpenWrt works on these finally and any iperf3 benchmarks for WiFi performance.