9:30am marked a shift in the trend for bond markets yesterday, and the same is true today. This time around, it's in an unfriendly direction. There are no fundamentals or headlines driving the weakness. Several block trades combined with volume data suggest sellers are stepping back into the bond market to short the lower technical boundary. This is roughly 2.20 in terms of 10yr yields.
10's are quickly up to 2.23--breaking even on the day. Fannie 3.5s are down a quick 6/32nds from the time some lenders released rate sheets. As such, those lenders are already potentially considering negative reprices.