Nope. Happened to me on the MacBook bore event thread this morning, for instance. That's only got about 110 posts.
One thought: when it happens on mobile, might it be due to a moment when the phone is slow on getting a last position reply from the server (either poor signal, or busy showing from 3G to WiFi or vice versa), gives up and just goes to its last known position?
Mind you, I've seen it happen at home too. But it seems the former case might be a trigger for some of the issues?
The same also happens sometimes with refreshing the Latest list of threads. That seems inconsistent on mobile, even on a solid WiFi connection and often requires a manual refresh.