QOD Part 2: Is January 31st, 2010 (the original date), the result of:
declare@StartDateTimedatetime;
SET@StartDateTime= CAST('2010-01-31T00:00:00.000' AS datetime)
SELECTDATEADD(MONTH, -3 , DATEADD(MONTH, 3, @StartDateTime))
SQL = Scarcely Qualifies as a Language