but I actually have two, both from September this year so it's hard to blame caching.
There are more people reporting this, e.g. here, but I do have a hunch why this happens in my case; this answer had been converted to a comment to the question, and was later undeleted by a ♦ moderator. See the timeline. Could it be that this event somehow doesn't propagate correctly to the network profile?
Browse other questions tagged bug answers network-profile .
Old network profile GUID URLs might redirect to wrong user?
In the annual rep league, why isn't the difference between rep earned this year and total rep always the same?