I’m not sure if this is an AppleTV issue, it’s more likely an issue on all platforms - feel free to move it to a better location.
Let’s say we have two AppleTV devices running infuse with a tv show: device A and device B.
A watches season 1 and stops watching at 50% of S01E03. B continues from that point and finished S01E03, he is now paused at 50% S01E04.
Now, what I expect to see on A is a synced version. Instead, A thinks it’s still on 50% of S01E03 and it also sees 50% of S01E04.
This was not the case on 7.x, which worked correctly.