How to choose a correct in-app type?

I've read all the in-app documentation and I've tired of fighting with App Review Board, that's why I'm asking for your advice.

Please, help me to choose the right type of in-app purchase for my app and to upgrade my app to use a subscription in-app model (non-renewing subscription is also possible).

This app has an entertaiment text and photo content, which is dynamicaly updated twice a day.

I've got a free version, which has:

1. Ads
2. Limitations (limited number of new messages)
3. No photos

And premium-account with:

1. No ads
2. No limitations
3. Photo content

I want to sell this content like subscription (you can buy a premium-account for a period of time), also I've get a mechanism, that allows to use premium-account from every device you have and you can restore your purchases easily, but App Review Board writes:

The App Review Board evaluated your app and determined that the original rejection feedback is valid. Your app does not comply with:

11.15

The Purchasability Type for one or more of your In-App Purchase products was inappropriately set.

Your In-App Purchase is currently flagged as Auto-Renewable Subscription. However, it would be more appropriate to use the Non-Consumable In-App Purchase type because the product is used to unlock features of the app. Non-consumable products are only purchased once by users and are always available on all devices that are associated with that user's iTunes account.

How should I change my app to sell my content as subscription?