This is very common for companies with holiday-linked or time-linked sales. It's much easier to make your big chunk of sales in Q1 (October-December for Apple), then have the rest of your fiscal year to spend that money. Getting all your revenue in Q4 is much harder to budget around.

BTW it is not 'exactly' September 30, it is usually last Saturday in September. So it does not even align at a 'calendar month' boundary.