There were two key parts to today's market movement.  The first was the general push back against Friday's bond market weakness courtesy of less upbeat details emerging in the US/China trade talks.  Long story short, China said it wants another round of talks before signing the phase one deal unveiled on Friday.  It also had at least one other stipulation regarding December's planned tariff hikes.  Bonds logically cheered that news, ultimately undoing ALL of Friday's domestic session losses.

The 2nd component to today's movement was an even bigger push back in the other direction courtesy of renewed Brexit optimism.  This hit European bonds like a sack full of quarters mid-morning but US bonds still got the nickels.  It didn't help that domestic equities markets also happened to be surging.  

Once yields crested Friday's levels, technically-motivated selling helped the weakness extend just a bit more and tha was that.  10yr Treasuries ended the day up 3bps in yields at 1.773% and Fannie 3.0 MBS fell about an eighth of a point to end at 101-03 (101.09).  

Tomorrow brings the week's biggest-ticket econ report in the form of Retail Sales at 8:30am.  Any big beat or miss is at risk of being traded accordingly (i.e. stronger data could keep upward pressure on rates).