If they checked the box on Step 2c; it will take out more taxes than without it being checked. 

The biggest change on the new 2020 Form W-4 is you no longer claim withholding allowances.  The more allowances an employee claimed on the old form, less tax was withheld.  As for the expectation on what the different amount would be, I do not have the specifics as it depends on what an employee has filled out on the form.  I would suggest reaching out to a tax advisor for more detailed information.