When you decide to make a "Bundle as a product ", if you set "Bundle as a product setting" to "Add the bundle as a product to the cart as a single product" you can set a selling plan for this new product that Fast Bundle creates for you and you see it in the "Products" section in your Shopify panel.

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In order to activate the subscription feature for this distinct product, go to your subscription app (like SUBIFY or RECURPAY) and set a "Selling Plan" for this product.

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