This KBA explains what Full Transmission Start Date(FTSD) is and the usage of the same.
SAP Cloud Platform Integration(CPI)
The full transmission start date (FTSD) is the date from which data transfer from Employee Central to the SAP ERP HCM system begins. It is used to determine from which start date on time slices are provided.
Example 1: In the below example, data record 2 and data record 3 are transferred; data record 2 starts from the full transmission start date. Data record 1 is not included in replication, because it is before full transmission start date.
Example 2: In below example, all three data records are considered for replication. Data record 1 starts from the full transmission start date.
The choice of the specific FTSD has some consequences for existing data in SAP ERP HCM - especially if SAP ERP HCM has historical data. During the initial full load from Employee Central to SAP ERP HCM already existing records in SAP ERP HCM are cut off at FTSD. This is a change in SAP ERP HCM that could trigger consecutive actions on the SAP ERP HCM side.
Recommendation Set the FTSD as high as possible, ideally to the date when you start to use Employee Central as the master system for organizational data (which could, for example, be your project go-live date). Make sure that employee master data replication and organizational data replication from Employee Central to SAP ERP HCM use the same FTSD. If you have decided on a FTSD, make sure that you no longer make changes that are valid before FTSD to data in Employee Central that is to be replicated to SAP ERP HCM. Data that has a last modified date that is before FTSD isn't replicated. Therefore, the data wouldn't be consistent in Employee Central and SAP ERP HCM.
If you've already set a full transmission start date and replicated data, we recommend that you don't move the FTSD to an earlier date. If you do so nevertheless, make sure that you trigger a full load manually to include all relevant data into the replication. The full load isn't triggered automatically.
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