Eviction after expiry of rental agreement

Our rental agreement of 11 months had expired on 27th June'16. Despite several conversations with the landlord to renew the agreement, he took his own time to think and did not renew the agreement till 7th Aug'16. Expecting something fishy, I had not paid the rent to him for the month of July and Aug (the agreement requires me to pay before the 5th of any given month) and on 7th Aug I informed him over an email that I would vacate the flat by 27th Aug. My questions are: 1) Since the agreement is not valid, am I entitled to give him a one-month's notice period (as stated in our agreement). If not, then is there any minimum notice period that I must give (considering the agreement is null and void)? 2) What are the obligations as a tenant once the agreement has expired and has not been renewed for more than 30 days? 3) I am not expecting him to refund any security amount which is 2-month's rent. I had asked him to adjust it against the rent not paid for the two months. However, he has been constantly sending email reminders to me to pay the rent immediately (almost every day). What can be done in such a situation? Since the agreement has lived its period and is no more valid, do any of the clauses apply in terms of notice period and arrears beyond a fixed date?