Both the Basic Authentication and OAuth 2.0 versions of the endpoints are currently live and operational. This means you can already begin testing and migrating to OAuth 2.0 without waiting for the sunset date.
While a specific cutoff date for Basic Authentication will be communicated in advance, there will not be a fallback option once it is officially deprecated. We strongly encourage you to start using the OAuth 2.0 endpoints now to ensure a smooth and uninterrupted transition.
