How to pin the PD Rest API schema version?

[henrycheung1]

Reading https://developer.pagerduty.com/docs/ZG9jOjExMDI5NTUy-versioning, it seems the accept header Accept: application/vnd.pagerduty+json;version=2 is insufficient to pin the PD REST API based on every schema update. (specifically this file: https://github.com/PagerDuty/api-schema/blob/main/reference/REST/openapiv3.json)

Would you have docs around PD Rest API versioning pinning and the available versions available? thanks