I thought I would post this here for posterity.
In September of 2016, my car’s backglass had a milky white look to the left most edge.
Since Sept 2016, my car has moved from CT to CA. It now lives in a garage whose temp ranges from 50F-90F. The car does not see precipitation, and has not been washed with water since 2016.
I was very surprised to realize that the milky look seems to have disappeared.... although some evidence of delamination remains.