Managed Timesheet Periods

[dave]

In our org. a week starts on Saturday. I changed this within "Customize Project Web Access". I also have managed Periods selected as the default. The timesheet periods provided on the form still starts on a Sunday. If after changing the 'week starts on' to Sat. i would have expected that the time periods also would have changed to Sat.
Am i doing something wrong?

Also, my timesheets are still not showing Sat as the start of the week.

And ideas?
thanks

dave