Today has quickly become the 3rd day of exceptionally calm trading relative to a heretofore tumultuous month.  The even-keeled vibes began right from the start of the overnight session with 10yr yields trading in a 2.12-2.14 range during Asian hours.  The onset of European trading brought even more stability and 10's narrowed to a ridiculously tight 1bp range until the GDP data.  By that time, MBS had begun the day 1 tick higher.

After GDP, both MBS and Treasuries had a small, but quick rally.  It's not unfair to say the day ended 10 minutes later.  We're at the exact same trading levels despite a bit of reaction to the Chicago PMI data at 9:45am.  Even then, bonds simply rallied and returned to previous levels.

In terms of technical levels, the lower bound for 10yr yields looks like 2.10 for today.  Anywhere between there and 2.12 could be considered "safely sideways" for the rest of the day.  Fannie 3.5 resistance kicks in at 104-15 and we've had multiple bounces there today.  Support becomes important at 104-12 in Fannie 3.5s and 101-08 in Fannie 3.0s.  In other words, the only thing to watch for the rest of the day in terms of risk would be for a break above 2.12 in 10's or below 101-08 in 3.0s (or 104-12 in 3.5s).  Other than that, if bonds break resistance (like 2.10 in 10's or 101-11 in Fannie 3.0s), keep an eye out for positive reprices that create lock potential.