Moving to SAP S/4HANA for an existing SAP ERP 6.0 customer will require a move to the latest enhancement package, followed by a database migration from anyDB to SAP HANA combined with the deployment of the exchange innovation (new code). From an execution perspective, these steps can be executed in sequence or as a combined step.
Moving to SAP S/4HANA for an existing SAP Business Suite powered by SAP HANA customer is even faster as only the deployment of the exchange innovation (new code) is required.