Webflow Membership Product Type Allow User to Change Variant

I have a Webflow Ecommerce membership type product that has 3 variants (free, basic, premium). Would like to enable the user to change variant (but only get free once). Currently cannot purchase another/change variant if a variant under the same product is chosen. I have evaluated memberstack, but for various reasons would like to keep webflow ecommerce. Any help would be appreciated! Planning to have many membership type products (potentially 1,000’s). Also comfortable with some coding so if you have ideas that require that would be great! Thanks!

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