5.5% coupon is at 100-31, the low of the day.  As the DJIA holds and/or progresses, there seems to be some selling pressure in MBS.  Not necessarily time to panic yet, but it may be soon if we drop further.

** Update, we've dropped another 2/32nds or so.  Locking may be the way to go if you cannot afford the risk.  (11:45AM).