Can I renew the lease agreement for 1 month till he pays balance

My self Gautham from Bangalore.Me and my family are living in a 2 BHK leased house .The leasing commence from 1-6-2013 to till 1-6-2016.The lease period 3 years .For 3 years lease I paid 9.5 laks in cheque payments. Now the leased due date are nearing and I want to shift to other area considering my son education.As per the agreement 3 months before only I had informed my landlord about my vacating the house. Initially he agreed to pay the full amount deducting only painting and cleaning charges approximately( 25k ) and the remaining lease amount he has to pay is 9.25laks Today he came and told me that he was able to adjust only 6.25 laks and remaing 3 laks I will give you a post dated cheque dating 25 of June(25-6-2016) and you please vacate the house before 1 june,so that I can give it for other tenant and the tenant is already ready. Now my question is I cannot wait till 25 june because my sons school starts from 1 June where I have already admitted him to the new area where we will be shifting , Mean while at any cost I should shift keeping my sons educations,also I cannot risk my hardly earned 3 laks in risk.I am worried what if the landlord doest not stick to his words or start postponing the days repayment of the balance amount. Please guide me in the following scenario . 1.Shell I renew the lease agreement and for another one month I mean till june end and also keep a duplicate key of the house with me and vacate .Also mention partment made by the owner i.e 6.25laks and also mention the post dated cheque details of the RS 3 laks . please guide me on this .Your help is appreciated My mobile number is 9008566111