Ultimately, it doesn't matter where in the calendar year you put the cut-off date. Regardless of which date you choose, there will always be almost a full year

Ultimately, it doesn't matter where in the calendar year you put the cut-off date. Regardless of which date you choose, there will always be almost a full year between the eldest and youngest students in any grade. Of course, it might matter to you, if you are expecting a child near the cut-off date for your region.