Bi monthly subscriptions

I am trying to take month payments but only send goods out bi monthly or on the third month is there a way to do this? The customer will pay monthly for an item but ti will only be sent out on the second month or they may pay monthly and the item sent every 3 months? It would be ideal if there was an order raised every month for accounting purposes but then the order on the 2nd (or 3rd) month would print out so we know to despatch the goods! Has any one else managed to do this?

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