Hmmm. First off, we need a more accurate placement of your receive location. Use
this method to generate the report by first entering your complete address (that will not show on the report.) On the resulting page, ensure that the receive location icon is pointing to the right spot. The map is a Google map, so you can zoom in as needed to get this right. Drag the icon to the right place as needed. Finish by clicking the "make radar plot" button.
Since you are apparently very close to the transmitters, I would have to guess that something about the path to that transmitter has changed, either eliminating helpful multipath or starting destructive multipath. I'll not speculate further until you post a new report.