To convert from yyyy-mm-dd to yyyy-mm you can use CDATE(date).ToString(“yyyy-mm”)
and use if condition to check if the mm increasaed or not if increased then incremenr the variable by 100
But I got a values for each months. Meaning there always will be a value when it’s Month-1 (Means last month is may until maturity date (assuming maturity date is 2028) there will be ALWAYS contain a value for each month). I never heard lambda query before, what is that? Also Maybe you can share workflow for this logic? Thanks