@Bob Day - interesting comments about the kelp spray, I am seeing conflicting information.
Does anyone else use Kelp Spray? According to sfgate:
https://homeguides.sfgate.com/fruit-tree-spray-peach-leaf-curl-59851.html - "Kelp sprays have been shown to worsen infection in some cases." However, here is the recommendation:
https://www.santacruzsentinel.com/2019/04/25/this-week-in-the-garden-restore-health-to-plants-after-wet-winter/
I don't know what to believe, but my necataplum tree (Planted 1 year ago in heavy clay soil (San Diego) has A LOT of leaf curl and the fruit are about the size of a dime so I'd imagine it's too late to use copper on the tree until next year.