update DATE with update query?

[fingersburnt]

I have a DB that records work done by staff in the week. i.e Monday-Sunday, Now after the sunday has passed currently user log in and enter the dates in the table start date, end date. Is there anyway to bypass this and use somesort of query to update this. So if I logged in on the following monday the previous Mon-sunday date will appear?

Or any other suggestions welcome

Thanks