Which command should an administrator run to initiate the license expansion for a blue-green upgrade...

Comprehensive and Detailed Explanation From Exact Extract:

During blue-green upgrades or license expansions in Portworx clusters, administrators use the command pxctl license expand --start to initiate the license expansion process. This command signals Portworx to begin applying the new license, enabling additional nodes or features as permitted. The process is carefully managed to avoid disruption during the upgrade and ensure that new license entitlements are recognized. The Portworx upgrade and licensing documentation specify this command as the official method for license expansion, ensuring compliance and seamless cluster scaling during complex upgrade workflows【Pure Storage Portworx License Management Guide†source】.