I have application that manage Contracts

I have "Contract sign date" field datatype = Date that have sign date

I have "pay type" field that have values "Annualy, Semi Annualy, Quartly"

I have "Contract duration" field datatype = integer that have contract duration (e.g. 3 years or 5 years or ... etc)

 

I will give an example for what I want:

 

Contract sign date = "01-04-2006"

Pay type = "Semi Annualy"

So, each payments will be every 6 months, the payment sequence will be 01-10-2006, 01-04-2007, 01-10-2007, 01-04-2008,01-10-2008

the payments are

 

I want to retrive the first value that is greater than now, from the previous dates will be 01-04-2008

 

I want the formula code, I know it will be loop, but I want to know how to do this loop

 

Thanks All