Ok , A little update and good news I think.. Apparently my last post was inacurate, I contacted teh Subscription people and they quote..:-
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You can always view the subscribed digital issues. Once you buy it, it is forever 
You would need the Pocketmags app to read them. Also, there isn't a way to download the issues to your hard disk or any other secondary storage.
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Also, the app is free and you will be only paying for the magazines. Since you have already paid and downloaded, it should not be an issue to view the magazines even after stopping the subscription.
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Must admit I find the 2nd paragraph intresting as if you can not download it , How are you able to view the magazine off line, which you can as I have tested it.. Strange things these apps…