You want to change the regional settings for a user (such as time zone, date format, etc.) via SDK (Employee After Modify).The corresponding fields are however only read-only enabled in the Public Solution Model.The same fields are editable on the UI, and they can also be updated using the Employee Replication SOAP interface.
SAP Cloud for Customer
Most of the fields, Which are allowed to edit or update via standard Webservices and UI are not PSM released. This is because, updating these fields through custom solution might cause inconsistency in the system.
Since identity BO is an Infrastructure BO, which belong to NetWeaver layer, it is not possible to make these fields PSM Enabled.
You need to use employee related services which were already provided in the system.
Employee, Identity BO, PSM Release, SDK , KBA , SRD-CC-IAM , Identity & Access Management , Problem