If you want to just swap a product, check this article out.
When logged in to your ReCharge Dashboard, select Customers and search for the specific customer you want to work with.
Once you click their name, you can click Add Product.
Once you've searched and selected the product from the menu, you will be able to set product parameters. This includes the frequency of how often it's delivered, the quantity, next shipment date, and which subscription it's being added to, existing or new.
If you're adding to an existing subscription, you may see a drop-down like in the following example. Add Product creates the dates on this screen by using the current scheduled queued charge date and then projects the additional dates.
Once apply our changes, it will be added to the subscription. If you're replacing a product with this one, be sure to delete the previous product. It may also be helpful for you to keep track of things if you add a search tag for 'changed product' or 'changed subscription'.
Note: If you choose today's date, you should then choose to process the charge manually. For details on how to do this, see our guide on Manually Triggering a Recurring Order Immediately.