Limit the members selection in EPMContextMember

Hi

I've used a formula =EPMContextMember so that user can choose the member in dimensions "B_TIME". It displays all members along with the hierarchy.

Should I want the selection for 2015.TOTAL and it's descendants, hiding all other years, how do I do that?

If I put the filter "PARENTH1=2015.TOTAL", it shows the Quarters but not the Periods / Months. I would need it to show the hierarchies and all descendants under it... in Hierarchy format / view, not just a list of members.