Is RCS registration part of 10DLC compliance and validation?

RCS is not tied to or part of 10DLC compliance and requirements, but it does follow a comparable flow.

If you want SMS fallback for RCS business messages and plan to register an RCS Agent and a new 10DLC number, you will have to complete registration and validation following separate flows and processes. 

For more information on 10DLC requirements and compliance, refer to the 10DLC Compliance Requirements and Guidance article.

For more information on RCS, visit the Sinch RCS product page.