Factory Calendar - Transfer Global Settings

Hi,

we have multiple source systems connected to a BW. Each source system uses its own subset of factory calendars, and we need all these calendars in BW.

If we want to transfer the factory calendar data (using transfer global settings), the only option is to rebuild the tables, an update is not possible (error message). So we can only load from one system, the next load would delete all previous data.

Does anybody know the reason for this restriction and/or a workaround?

Any help is appreciated

Regards

Stephan