It's a hybrid of formosanum which I also have and you can see the similarities in the shape of the pouch and also in the leaf shape (even though the leaves have several up a stem, rather than just two at the top like formosanum, you can still see the similarity there).
I really love these flowers, so hoping this one does well for me in future years. Only this one and my formosanum have done well this year and one seems to have disappeared over the winter