Does date mentioned on agreement form have any importance while filing complaint against builder

Hi there, 

I am planning to buy new property in my area for which the RERA completion date is Mar-2029 but builder is ready to mention the possession date as Dec-2027 on Agreement form. So I just want to ask, the date mentioned on Agreement form holds any importance while filing complaint against builder in case of delay in possession or the date which is mentioned on RERA will be considered and my complaint will get rejected?