I believe it is drought stress, has to be.
Several trees had a complete bloom earlier this year but on about 4 varieties, could be more, I am seeing a few panicles on parts of the tree not holding fruit. The only stressor I can attribute it to is drought.
This coupled with significant fruit drop has me watering many of my smaller trees, even a couple of larger ones.
By the way, one more things the drought has done is keep disease pressure down, most varieties in my yard have pretty clean fruits. If this your experience as well?
I walked out to take a couple of pictures for this post and it is drizzling. Didn't last long but it may be a sign for a wet weekend.

Thom Pi Kan that I grafted back in 21 (from a forum members collection). Still only about 2 feet tall and will not be allowed to hold fruit but flowered instead of pushing new growth.

Several varieties on this tree (the nurse tree) but I believe the flowers are on an Orange Shubert branch and a Malika branch with Ruby out of the frame but about to explode on just about every tip on the branch..
This is not unusual for my Choc Anon and it is doing it again. It usually holds fruits from 2 or 3 different blooms. Beverly also has a couple of flowers so does Malika and Carrie.
Are number of trees and some of the same trees are flushing new growth which is what I was expecting.