3786033 - ASSIGN_TYPE_CONFLICT dump in generated RSDS program when loading from a datasource of type FILE

The below dump occurs when running a DTP extracting from a datasource of type FILE:

"Category               ABAP programming error
Runtime Errors         ASSIGN_TYPE_CONFLICT


8        METHOD    FILL_DTIS    CL_RSDS_X_CMD=================CP
7        METHOD    GET_DATAPACKAGE_FILL_DTIS    CL_RSDS_X_CMD=================CP
6        METHOD    IF_RSBK_CMD_P~CHANGE_ALL    CL_RSDTIS_FILL_CMD============CP
5        METHOD    PROCESS_REQUEST    CL_RSBK_PROCESS===============CP"

BW/4HANA

KBA , BW4-DM-SRC-FILE , File Source System , Problem