When it's working I see this in my ifconfig output section of wlan0. Note I've removed macs and ip's.

wlan0: flags=1008843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST,LOWER_UP> metric 0 mtu 1500
options=0
ether *:*:*:*:*:*
hwaddr *:*:*:*:*:*
groups: wlan
ssid Smithies channel 100 (5500 MHz 11a) bssid 04:f4:1c:8d:60:71
regdomain ETSI2 country GB authmode WPA2/802.11i privacy ON
deftxkey UNDEF AES-CCM 2:128-bit AES-CCM ucast:128-bit txpower 23
bmiss 7 mcastrate 6 mgmtrate 6 scanvalid 60 wme roaming MANUAL
parent interface: iwlwifi0
media: IEEE 802.11 Wireless Ethernet OFDM/54Mbps mode 11a
status: associated
nd6 options=29<PERFORMNUD,IFDISABLED,AUTO_LINKLOCAL>
And when it's not and I get no link to network:

wlan0: flags=1008843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST,LOWER_UP> metric 0 mtu 1500
options=0
ether *:*:*:*:*:*
hwaddr *:*:*:*:*:*
groups: wlan
ssid "" channel 1 (2412 MHz 11g)
regdomain ETSI2 country GB authmode WPA1+WPA2/802.11i privacy MIXED
deftxkey UNDEF txpower 30 bmiss 7 scanvalid 60 protmode CTS wme
roaming MANUAL bintval 0
parent interface: iwlwifi0
media: IEEE 802.11 Wireless Ethernet autoselect (autoselect)
status: no carrier
nd6 options=29<PERFORMNUD,IFDISABLED,AUTO_LINKLOCAL>
I'm also right next to the AP so both 2.4 and 5G signals are very good.

CC: @nprofile1q...