Non-renewing subscription end date

I'm developing an iOS app with a non-renewing subscription. We want to use MKStoreKit to handle everything related with IAP. My understanding is that we've to manage "manually" when the subscription is finished in order to don't show the premium contents to the users.

• How can this be done if nothing is stored in our servers?
• Can we check (somehow with MKStoreKit) the subscription date in order to calculate the ending date?
• If users have several devices, we guess we'll need to implement the "restore" method so all the devices will be able to see the premium contents, no?
• And what happens if once the first subscription is over, a user decides to subscribe again? Will we know both beginning dates? just the last one?

Thanks!

via Chebli Mohamed