You found the Status/Item Status was changed by user SAP_SYSTEM, this can be checked from Changes tab.
SAP Cloud for Customer
There is a background job AP_CTR_SET_STATUS_FOR_VALIDITY running every 30 minutes in each customer system.
This job is executed by the technical user SAP_SYSTEM.
The purpose of this job is to set the status of a Contract (Item) from Ready to Active, when the current date reaches the start of the validity period and to set the status of a Contract (Item) from Active to Obsolete, when the current date reaches the end of the validity period.
Also, In order to change the status, the Contract has to be modified and saved. Hence all PDI coding which is registered to be executed for AfterModify, BeforeSave, OnSave, etc. will be executed as well.
This is working according to standard design.
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