Welcome, Colleen!
Are the fruit turning yellow, or the leaves? If the leaves are turning, are the newer leaves turning greenish yellow, with darker green veins, or are older leaves (possibly way too many) turning bright chrome yellow and dropping off?

are there yellow veriaties perhaps ?

There sure are yellow varieties, particularly of Japanese Plum, but they shouldn't be ripening yet.

ow i see you learn something everyday tugbrethil . in that case it sounds like the fruit is dying or ripening early x .