1. SAP S/4HANA Help Portal
"Margin Analysis": "The key benefit of margin analysis is that the accounts and margin analysis are always reconciled. This is because margin analysis is directly integrated with the general ledger... For example
when you post a goods issue for a sales order
the cost of goods sold is posted to the corresponding account and immediately visible in margin analysis." (This describes the real-time update at goods issue).
2. SAP S/4HANA Help Portal
"Costing-Based Profitability Analysis - Flow of Actual Data": "When you post a billing document in Sales and Distribution (SD)
the data is transferred to Profitability Analysis (CO-PA)... The system creates a line item in CO-PA for each billing item and writes this to the segment level." (This confirms that the update to costing-based CO-PA occurs at billing).
3. SAP Learning Hub
Course TS4F04 - "Controlling in SAP S/4HANA": Unit 5: Profitability Analysis
Lesson: "Data Flow to Margin Analysis". The course material explains that the goods issue posting (movement type 601) triggers the COGS posting
which is immediately reflected in Margin Analysis via the Universal Journal. In contrast
the lesson on "Data Flow to Costing-Based CO-PA" specifies the transfer of the billing document as the trigger point for updating COGS value fields.