You can perform the following activities in the Product-Specific Configuration Phase in SAP Central Business Configuration: modify building blocks, change approval thresholds, and add blocking reasons for billing. The Product-Specific Configuration Phase is a phase that allows you to configure and customize your SAP S/4HANA Cloud system using predefined building blocks and self-service configuration UIs. You can use the Configure Your Solution app to access the building blocks and UIs for each product area and scope item. You can modify building blocks that contain the configuration settings and data for a specific business process or function, such as company code, fiscal year variant, or chart of accounts. You can change approval thresholds that define the limits or conditions for approving certain business transactions or documents, such as purchase orders, invoices, or payment runs. You can also add blocking reasons for billing that prevent the creation of billing documents for certain sales orders or deliveries due to specific reasons, such as credit limit exceeded, incomplete data, or dispute.