169.254.1.1 is the default backdoor IP address of the ePMP device. This is the management IP that is always reachable from the ethernet interface regardless of the radio configuration.
If you'd like to use this IP for the bridge IP, then consider changing the backdoor IP address to something else. Details of how to do that can be found here: http://community.cambiumnetworks.com/t5/ePMP-Configuration-Management/How-to-block-the-back-door-ip-address-on-ePMP-radios/m-p/57333#M26