Fannie 3.5s are only down 4/32nds (still up 1/32nd on the day at 100-29) from the earliest rate sheet print times, but bond markets have been trending slightly weaker over the past 2 hours.  10yr yields have risen from 2.575 to 2.589 during that time.

While this isn't much of a move, lenders who didn't price conservatively this morning could increasingly consider negative reprices if we lose any more ground.