When using kubeip to manage a reserved external IP that is of STANDARD tier, the gcloud compute instances call fails with the error

ERROR: (gcloud.compute.instances.add-access-config) Could not fetch resource:
 - External IP address: xxx.xxx.xxx.xxx has a different network tier STANDARD from the network tier in instance access config PREMIUM.

According to the docs, there is a parameter network-tier which is PREMIUM by default, and seeing the source code of kubeip that is the value being used by the command, as no value is specified in the function call.

A proposed solution would be to check the NetworkTier attribute of the retrieved GCP Address and if it is of type STANDARD, setting the parameter value to STANDARD for these cases would fix this issue.