BI-IP: Change of characteristic value in ABAP EXIT planning function

Hi

I have created a planning function of the type EXIT with reference data without blocks. In method IF_RSPLFA_SRVTYPE_IMP_EXEC_REF~EXECUTE I am going to implement my code.

Now, one of the purposes is to update the VALIDTO of an existing record. Is it possible to modify the characteristic values directly in C_TH_DATA (thus allowing me to just update the date directly on the record) or can I only append records?

Cheers!

/Karsten