Starting around 12:15pm ET and accelerating quickly at 12:25pm, bonds began a sharp rally, led quite clearly by the short end of the yield curve and Fed Funds Futures. In this short time, year-end Fed rate expectations dropped from 3.60 to 3.56.  That may not sound like a lot, but it's the biggest move over such a short time window in over a month.

10yr yields are now down 4bps at 3.987 and MBS are up 3 ticks (.09).  We'll circle back if we get clarity on the underlying mover.  To be sure though, it is not a currently published news article or anything else on the normal beaten path (not yet anyway).