It’s September 1, which, as we all know, is the day that fictional British wizarding children find themselves on the Hogwarts Express, heading back to school. It’s also September 1, 2016, which isn’t a special day at all… but everyone got confused about that this morning, thanks to J.K. Rowling.
Source: io9 – Even J.K. Rowling Can’t Get the Harry Potter Timeline Right