You should figure out how to fix the way it appears in the MAS listing, it's going to cost you a lot of downloads among a savvy audience. I always check that IAP section on free apps before I bother downloading.
I get why the previous subscription option would still appear, but I'm not sure why the one-time option wouldn't be appearing. Maybe not enough transactions on it yet?
latest version is one time purchase now
trying to keep it simple and local, no uploads and no ongoing fees