Clearing data from smartsheet before data uploader runs
I have a smartsheet that I am populating monthly with a job from data uploader. The smartsheet has several columns that are manually updated between uploads. For example, January the uploader will run and import data to overwrite existing data in Rows A-C in Columns 1,2,3. Column 4 will be manually updated sometime after the uploader has run. In February the uploader will run again and overwrite Rows A-C in columns 1,2,3. But column 4 will still contain the manual entry from January that is no longer relevant. How would I get this automated so that when the smartsheet is updated, the other column will be blanked out to start fresh with the new months data? Hope this makes sense!