I would like to get 20gb on Ubuntu One, but I am not at ease with the idea of storing my account information for the purpose of automatic renewal. Is there a way of acquiring the one year service so my information is only submitted once and not stored.
I am on a monthly subscription plan with Ubuntu One and every month I have the option to cancel the subscription which will then run until the day I have paid up to. For example :
1st July until 1st August If I cancel on the 2nd July I will still have access to my 20GB until the 1st August.
If you purchase the yearly package and then view your account I am pretty sure it will work in the same way. If you were to cancel the subscription you should still be able to use your service without your card details being stored.
I would clarify this with UbuntuOne by going here https://one.ubuntu.com/support/contact/
On another note, your credit card information is secure and they will soon be introducing the option to pay via pay-pal.