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.
That bit me at first as well. I ended up changing our 'default config' file that we push to every radio before deployment so that the pre-assigned IP is 10.1.1.254, leaving the backdoor at 169.254.1.1. (for APs I change the backdoor to 169.254.1.2) It still answers to 169.254.1.1, which our techs are trained to expect out of the box.
you can change the backdoor IP via cli as Sriram's post points you to, or you can edit/add the field ""networkLanDefaultIP": "169.254.1.1" in a JSON config file (or via cnMaestro), or set it via SNMP as "networkLanDefaultIP.0".