It is funny you mention a hybrid of the 'White Butterfly'. The first late-summer/early-fall that I had the 'White Butterfly' there were luna moths feeding on the nectar. The moths came out at dusk and stay around for a couple of hours after dark. The hummingbirds had all left, and at first I thought the moths were some sort of "new" hummer. The moths are about the same size as hummingbirds. Now the moths come every fall. They are interesting to watch, particularly since I have flood lights above one patch of 'White Butterfly' and the moths dart into and out of that light.
Do you have a picture of what the 'Luna Moth' looks like? What's the difference with this hybrid and the 'White Butterfly'?