Once you enter your Comp Time:
Click "Save for Later" if you do not require pre-approval for the time and submit it once you are ready to submit your timesheet on Tuesday.
Or
Click on "Submit" if you need to have your manager approve it prior to the Timesheet Tuesday.
Note: when you click submit you will submit all time entry. It will be up to the manager to approve just the comp time and wait to approve the whole timesheet once completed. It will not be an issue for you to submit the timesheet once completed on Tuesday. It does not duplicate.
Click the Save for Later button.