Hi, I’ve been having an issue as of upgrading to 11.1 on iOS (iPhone 8).
When swiping left on a story in the All Stories feed, often the marking as read registers on a different item, usually the one that’s two or three down in the list but sometimes above the swiped item.
It’s not every time though - I haven’t worked out the trigger for the issue but it seems to tend to happen early after the feed has refreshed.
Thanks for having a look!