Hi Kyle!
The value of subscription_discount will depend on how your product object is structured. Lets say your selling plan applies a 10% discount, then the discount amount for item.product.subscription_discount_amount would be '10.00'
Here are some things you can try calling in the console:
Rebuy.SmartCart.items()[0].product.subscription_discount_amount - Returns the subscription amount of the first product in cart
Rebuy.SmartCart.settings.switch_to_subscription.language.upgrade_to_subscription_label - Returns the input of what's set under Upgrade to Subscription Label. In your case, it's "Upgrade to Subscription & Save {{subscription_discount}}%"
Rebuy.SmartCart.switchToSubscriptionLabel(Rebuy.SmartCart.items()[0]) - The switchToSubscriptionLabel function essentially replaces {{subscription_discount}} with the item.product.subscription_discount_amount value, which then outputs the label as "Upgrade to Subscription & Save 10%"
