Can't upgrade to pocketcloud pro

Can't upgrade to pocketcloud pro

I have had pocketcloud pro for android for the past few years, with good functionality.

My new phone is an iPhone 6 plus, with iOS 8 updated to 8.1.

I decided to try the free version to make sure that it worked with iOS 8 before purchasing, as the release date was a few months ago. 

The app seems to function fairly well, so I went back to the App Store, but couldn't find the Pro version, and there doesn't seem to be any way to upgrade via in-app purchase. I am not interested in the Premium subscription version. 

No standalone Pro version is available on iTunes, either, although I thought that both versions (free and Pro) were available in the App Store when I was setting up my new phone. 

I tried uninstalling the free version, but only the free version seems available in the App Store.

iCloud might have something to do with this problem, since the app doesn't show up in the App Store with a blue rectangle outlining "FREE", but a cloud icon, with a blue arrow pointing downwards.

Signing out of iCloud will erase Apple Pay data for credit cards, etc., which will require time to reconfigure, so did not seem a good option, particularly if not successful.

One of my friends has a similar iPhone 6 plus, updated to iOS 8.1, has never used pocketcloud, and only the free version shows up in the App Store. iCloud is also activated on that phone.

How do I upgrade to the Pro version?

Thanks