Change IP Address UBNT via SSH

Mode Bridge

ifconfig br0 192.168.100.100
route del default gw
route add default gw 192.168.100.254 br0

Mode Router

ifconfig ath0 192.168.100.100
route del default gw
route add default gw 192.168.100.254 ath0

Save Reboot.

cfgmtd -w -p /etc/
reboot