Thanks! I understand now. I was able to flash with the img provided using the instructions above (Debrick via Uboot - GL.iNet Docs).

I then found that the factory img did not contain luci so I had no web UI.

So I did:

scp openwrt-ath79-nand-glinet_gl-ar750s-nor-nand-squashfs-sysupgrade.bin root@192.168.1.1:/tmp/
ssh root@192.168.1.1
sysupgrade -v openwrt-ath79-nand-glinet_gl-ar750s-nor-nand-squashfs-sysupgrade.bin

However, this also doesn’t have luci:

root@OpenWrt:~# opkg list-installed | grep luci
root@OpenWrt:~# 

This is a bit off topic now - but I do I understand correctly that I should install luci manually for this image?

Thanks again for your help.