Rent increased as per agreement

Dear Friends,

                     we Have Taken Many Flats for our Staff Accomodation, Rent Agreement have been Prepaired for 11 Months only for Each Flat, but There is a Point in Each Agreement that Rent Will be Increased @ 10% Annually.

                      For Example we have Taken a Flat on 01.01.2017 for 11 Month, Agreement Period Will be 01.01.2017 to 30.11.2017...... Then my Question is Increment will be Applicable Weather from Dec"2017 or Jan"2018..... Please Suggest