Okay, with no immediate replies, I have run IP ROUTE on each of my devices; output is below:
root@GL-AR750:~# ip route
default via 10.0.0.1 dev br-lan proto static
default via 10.0.0.1 dev wlan-sta proto static src 10.0.0.40 metric 20
10.0.0.0/24 dev br-lan proto kernel scope link src 10.0.0.50
10.0.0.0/24 dev wlan-sta proto static scope link metric 20
root@GL-AR750:~#
root@MT300N:~# ip route
default via 10.0.0.1 dev br-lan proto static
default via 10.0.0.1 dev wlan-sta proto static src 10.0.0.45 metric 20
10.0.0.0/24 dev br-lan proto kernel scope link src 10.0.0.55
10.0.0.0/24 dev wlan-sta proto static scope link metric 20
root@MT300N:~#
From a PC connected to MT300N:
IPv4 Route Table
Active Routes:
-------- Network_______ Destination Netmask ___Gateway Interface _______Metric
0.0.0.0 0.0.0.0 10.0.0.1 10.0.0.11 20
10.0.0.0 255.255.255.0 On-link 10.0.0.11 276
10.0.0.11 255.255.255.255 On-link 10.0.0.11 276
10.0.0.255 255.255.255.255 On-link 10.0.0.11 276
127.0.0.0 255.0.0.0 On-link 127.0.0.1 306
127.0.0.1 255.255.255.255 On-link 127.0.0.1 306
127.255.255.255 255.255.255.255 On-link 127.0.0.1 306
224.0.0.0 240.0.0.0 On-link 127.0.0.1 306
224.0.0.0 240.0.0.0 On-link 10.0.0.11 276
255.255.255.255 255.255.255.255 On-link 127.0.0.1 306
255.255.255.255 255.255.255.255 On-link 10.0.0.11 276
Hope that’s readable.