There's a lot of bugs with Festival Plaza and online features overall. There's these ranking issues you mentioned and I'm having a nightmare of a time once again with GTS. How long do they usually take to develop needed patches? I don't remember the first X and Y patches taking this long.
I know that X and Y didn't take long is because of the gamebreaking glitch that immediately needed to be fixed. Unlike then, Sun and Moon doesn't have severe bugs that needed a fix ASAP.