Definition of lease period

In leases/ leave and Licence agreements the period of 11 months has become very common for many reasons. But how is the period of 11 months calculated. The problem is when the existing Tenant under an agreement expiring soon wants to ensure renewal of the licence for another 11 months.In that case practically the date of execution will be one, and effective date commencement of leave and licence will be a few days or months later. EXAMPLE ONE. Date of signing initial contract 1st April 2016 with effectuve date of commencement of lease period of lease of 11 months as 1st of May to end on 31st March 2017, EXAMPLE TWO .Now, the parties for reason of continuation of the renting and occupancy desires to extend. Suppose, they enter into a fresh agreement on 1st January 2017 with an effective date from (Option A )1st april 2017 or (option B) 1st May 2017 which is more safe and what is the efect on the 11 month restriction? First option is continuous and second option is with a GAP segregating the old expired contractual period!