Japanese Pink Cherry Fruit Shape?

[groovy70s]

I'm growing Japanese Pink Cherry this year and I'm getting two distinct shapes of fruit on the same plant. I have two plants and both are producing apple/heart shaped fruit and also the oblong or grape shaped fruit. Both shapes are on the same truss actually. The fruit is definitely pink (clear epi) so that part is true to the type at least. Does anyone know if both shapes of fruit are normal for Japanese Pink Cherry or is it possibly not stable or possibly it was crossed somehow in someone's garden before the seeds got to me? See my pics for the two different shapes of fruit it's producing. Thanks for your help.