SSAS Grand Total And All Level for LastChild Measure

Hi,

I have a standard time dimension hierarchy Year->Quarter->Month->Date and a semiadditive measure with LastChild as the aggregation.

I've written scope statements for current month,current quarter and current year level  to show the correct values (last available date at which data is populated). This way the totals and grand totals are working fine.

For example : Month Level

                 Nov 2012      Dec 2012         Jan 2013          

Measure    20                    30                      40


But when i don't select current timeperiod(by filtering the members)  the scope statement at all level overwrites the above grand total


                 Nov 2012      Dec 2012         Grand Total          

Measure    20                    30                      40   (it should show 30 since december is the last selected month)


1) So is the grand total and the "All" Level both same in ssas?

2) Is there a way to tell the scope statement at all level not to update the grand total?