Game Freak’s Junichi Masuda has provided the location of where you can find out tomorrow’s Pokemon Sun and Moon news, via his personal blog. Fans looking for the new Pokémon Sun and Moon info can head to the official Pokémon Company YouTube accounts. Here’s the Japanese one, and here’s the English one. Although he specifically mentioned the former, it’s likely that the other accounts that are in different languages will get the info too.
He also posted what times you can expect the information at in your time zone. If you live on the East Coast of the United States, it will be announced at 8:00am. The West Coast will get the info three hours earlier, at 5:00am. If you live in London, it will be 1:00pm.