Sometimes. If you are updating an active submission that we have marked as "broken", or is less than 12 hours old, then there is no fee. Otherwise, there is a $6 fee for each active submission you select. Make sure you choose which active submissions you would like to update in step 2 when updating your project.
If there are no active submissions to select, or you do not want to update any active submissions (and just update the project as a whole), then there is no fee.