Unless I see clear evidence of an abscission zone separation I'm not calling it blossom drop.
The zone is the little joint just behind the blossom.
Just in case you dont know what it is here is the link to what I am talking about and explanations why it happens.
It is also the place that trees separate their leaves in the fall.
https://www.google.com/url?sa=t&rct=...dMz4ynLsftzyVp