In the United States at least they would not be able to do that. They would need to give you your previously purchased content without the monthly fee. They could start charging a monthly fee, but it would have to apply to new content only. If they tried to do it the way you suggest, they would have a huge lawsuit on their hands.
Back to Mount and Blade...
Where can I ransom captured lords? And I think the most fun I have had in the game so far is recruiting the Peasant girl "Ymira" and turning her into an all out warrior
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