Passport APIs follow standard Semantic Versioning 2.0 rules. When there are breaking changes to an API, Passport will release a new major version of that API.
Major versions are reflected in the URL path of the API. The implication being that two backwards-incompatible versions of an API will have two different URL paths:
New releases of an API version will be accompanied by a change log that documents the new capabilities and incompatible differences with the prior version.
API Lifecycle Policy
Passport APIs are designed to minimize the need for backwards incompatible changes, but while these types of changes should be rare, they are not unexpected as Passport expands its capabilities and adapts to the rapidly shifting mobility landscape. When a new version is released, Partners will be given advance notice and the current API version will be assigned a deprecation period per Passports API Lifecycle Policies. The deprecation period will allow Partners ample time to plan for and migrate to the latest version. The Lifecycle Policy will be shared with Partners upon registration.