First date of Current Quarter MDX - mdx

Question

I am trying to convert some T-SQL queries into MDX:
I require the first date of the Current Quarter for our reporting solution.
Within the cube we have a dynamic 'Current Quarter' flag
This seems like a simple problem but it has caused me no end of issues. I've managed to isolate the correct date but with the query below but in SSRS I get an error that states 'The default value for StartDate is not the expected type' i.e. it is not in DateTime format. This leads me to believe it is being passed as a string
How do I modify the following query to pass the StartDate as a DateTime and not a string?
The second piece of code is a secondary attempt at the same thing except I get the first value of the entire Date dimension (1900-01-01) instead of the first day of the current quarter.
First attempt:
SELECT
NON EMPTY
{} ON COLUMNS,
HEAD(
[Date Lead Date].[Calendar Date].[Calendar Date]
,1) ON ROWS
FROM [Leads]
WHERE [Date Lead Date].[Current Quarter Flag].&[1]
Second attempt (produces 1900-01-01):
WITH
Member [Measures].[StartDate] AS
HEAD(
[Date Lead Date].[Calendar Date].[Calendar Date]
,1).ITEM(0).ITEM(0).NAME
SELECT
NON EMPTY
[Measures].[StartDate] ON COLUMNS
FROM [Leads]
WHERE [Date Lead Date].[Current Quarter Flag].&[1]

Answer 1

Untested but I'm wondering if this works?
WITH
Member [Measures].[StartDate] AS
[Date Lead Date].[Calendar Date].CURRENTMEMBER.MEMBER_VALUE
SELECT
NON EMPTY
{[Measures].[StartDate]} ON COLUMNS,
HEAD(
[Date Lead Date].[Calendar Date].[Calendar Date]
,1) ON ROWS
FROM [Leads]
WHERE [Date Lead Date].[Current Quarter Flag].&[1]