Premieres in Japan on October 25th. The PV is here. Check out the ANN article for additional cast/staff information. Short synopsis of the source novel from the ANN article:
The novel centers on the members of a boat club at a girls high school in Matsuyama city in Ehime prefecture.
That explains why I thought the characters in the image on the post were 3DCG. That’s unfortunate. It can be done well (looking at Land of the Lustrous for example), but most of the time it’s not done well.