I´m living in São Paulo, Brasil, where the winter is more rigorous than in Rio de janeiro, place from where the pitangatuba is native. I have three pitangatubas, being one of the elongated fruit and two of the rounded fruit. The elongated var has flowers all year, but in less quantity in autumn and winter. The rouded vars are more erratic, and usually don´t have flowers in winter.
As a side note, you don´t need two trees. Just one will set fruits, but in less quantity.