https://cloud.google.com/compute/pricing#ipaddress говорит:
Выяснить неиспользуемый:
bash# gcloud compute addresses list
NAME REGION ADDRESS STATUS
artifactory-2-vm europe-west1 10.132.x.x IN_USE
artifactory-2-vm-pub europe-west1 35.210.x.x RESERVED
artifactory-2-vm-public europe-west1 35.210.x.x IN_USE
Удалить неиспользуемый:
gcloud compute addresses delete artifactory-2-vm-pub --region=europe-west1