The extenders are these:
I can’t recall make/model of mancave router but think it’s a Netgear. It should have DHCP disabled. I have devices down there working with a static IP assigned by the Telstra router.
Next time I’m down there will give it a look. Will also try to log into it to check on set up. Even so it’s down the hill and inside a besser brick building and there is no signal from it up here.
Ultimately I may need to rip what I have out and start fresh with an alternative. I didn’t find the 4G backup options suggested on WP particularly appealing.
Speed of the router is not a bottleneck here, the NBN fixed wireless is way slower than anything I might connect to it.