Corporate debt issuance is a net negative for bonds.  There was a lull in issuance heading into Thanksgiving.  With traders snapping out of holiday mode, it makes sense to see new issuance coming to market. It all seems so obvious in retrospect, but bonds apparently hadn't priced in enough of the issuance risk. 

At least some credit for that goes to Amazon for unexpectedly announcing a massive multi-tranche offering (Amazon's last 3 corporate bonds have been in April, May, and June respectively).  With that, MBS are already down more than 3/8ths of a point and 10yr yields are well on their way back into the middle of the prevailing trading range after pushing the lower boundary for the past 3 sessions.

In other news, the new conforming loan limit is out for 2023: $726,200