1Password for Safari 8.12.6 picks wrong default entry to autofill

My public domain is xxxxx.org.uk. In 1Password I have many entries for various self-hosted things all of the form:

YYY.home.xxxxx.org.uk

where YYY differs for each item. Since updating to the 8.12.6 TestFlight version of the Safari Extension (to avoid the issue where autofill does not work at all on many sites) I now find that If I am trying to log in to web page at, say:

aaa.home.xxxxx.org.uk

for which I have a dedicated 1Password entry then the extension offers as a default the entry for

qqq.home.xxxxx.org.uk

and I have to open the drop down list and manually select the correct entry.

This was never an issue previously.