i have a free 5 GB plan. My photos are 30 GB. What happens if I do the following: 1. Subscribe for the 60GB plan by paying for 1 month. 2. Back up my photos on iCloud. 3. Cancel my plan. So I get the proportionate refund 4. Subscribe the plan when I require again. 5. Follow step 2-5 repeatedly. Can it happen that I effectively don't pay anything by the method and I can get a backup whenever I want?