I seem to be getting some strange results when I use the "Get New Threads" option these days. Very often it gives me the "The threads below have not been updated ...." line above threads that definitely do contain new posts since my last visit, and this morning I noticed some weird timestamp stuff. See attached screenshots and check the date and times (wrong in both cases!).
The only thing that comes to mind is that this is a work PC, and my internet connection is probably routed internally through god-knows-where. Never noticed a problem before though.