There is a -TruncString option, but I doubt that would fix the problem.

If that doesn't help, define an extra column in the landing table and use the -fillrecord option,  Ignore the extra column.  This assumes you are using NZLoad and bringing data into staging and can change the staging table definition.

If you are using an external table definition, just add the extra column, add -fillrecord,  and ignore the extra column in your SELECT query.