Billing of Magazine Subscriptions on iTunes

Hello

I understand that the answer to the question may seem somewhat obvious, but since I'm dealing with a fairly substantial amount of money (in my respects), I just want to be 100% sure first before committing.

I have 2 yearly rolling magazine subscriptions with iTunes (~£70 in total), although recently I had to cancel the credit card I had tied to my iTunes account. I haven't added another credit card and from now on, I'd rather use iTunes cards wherever possible to credit my account.

I just wanted to the assurance that if I was to purchase £75 of iTunes cards and "upload" the credit to my account, will this credit then be used when we reach the renewal dates?

Thank-you for your assistance