This can occur if the files being sent from IWS to the AAI IWS Connector, contain trailing spaces at the end of each line, specifically the baseobjs file.
If using SFTP to transfer their files, your SFTP command file should contain a USS "cp" command to copy the MVS dataset into a USS file before sending that file via SFTP, in the format - !cp -T "//'HLQ.BASEOBJS'" /uss_dir/baseobjs
This will strip the trailing blanks during the copy process from MVS to USS, eliminating the cause of the Forecasting issue