MBS are still in positive territory on the day, but have given up most of the gains.  2.5 UMBS coupons are down roughly 7 ticks (.22) from the highs and down at least an eighth of a point from the well-traded plateau that had been intact for most of the day. 

Some of the more aggressive lenders may be considering negative reprices although risks aren't necessarily high.  The best way to use this alert would be to treat it as a lock cue if you were already planning on locking today (especially if your rates are noticeably better than they were yesterday).