I have an A4 R4AC model chinese verison so I flashed with with https://openwrt.org/toh/xiaomi/mi_router_4a_mir4a_100m
however I dont see the 5ghz interface when I run
root@OpenWrt:~# iw dev
phy#0
Interface wlan0
ifindex 4
wdev 0x1
addr *********************
type managed
txpower 24.00 dBm
multicast TXQ:
qsz-byt qsz-pkt flows drops marks overlmt hashcol tx-bytes tx-packets
0 0 0 0 0 0 0 0 0
root@OpenWrt:~#