When you upgrade from the $40 to the $100 option, do you get credit for the $40 already paid, or at least part of it??
First, I think 50 GB doesn't represent a well engineered system. I have a 64GB iPhone, so iCloud cannot back up my entire phone if I end up using what it has. For $100 per year, Apple should offer 100 GB like Dropbox does now.
Anyhow, I had to upgrade from the $40 plan because I didn't have enough storage to back up my iPhone. Apple automatically charged me $100, and it didn't appear I was given any credit for the money I had already paid.
iPhone 4S, iOS 6