GCP always free tier has restriction on regions for GCE

From this document https://cloud.google.com/free/docs/gcp-free-tier, It has restrictions on only 3 US regions:

Oregon: us-west1

Iowa: us-central1

South Carolina: us-east1

But the overview page says all US regions excluding Northern Virginia [us-east4]
Which one is correct?

Related lesson: https://acloud.guru/course/gcp-certified-associate-cloud-engineer/learn/services/gce-in-and-out-lab/watch