Prorated plan upgrades that honor promotional discounts

What would you like Navexa to do? Introduce prorated plan upgrades that honor active promotional discounts. When a customer on Basic with a promo (e.g., 30% off) upgrades to Standard mid-cycle, charge only the discounted difference for the remaining term—instead of the full Standard price. Why would this be useful? Prevents overcharging and confusion when upgrading during a discounted period. Reduces manual support work (refunds + special invoices) and speeds time-to-value. Aligns billing with common SaaS expectations, improving trust and retention. What would the ideal outcome look like? During an upgrade from Basic to Standard, the system computes a prorated credit for unused Basic time at the discounted rate and applies the same promo discount to the Standard cost for the remaining term. The user pays only the net, discounted difference. The checkout clearly itemizes: prorated Standard cost, applied discount, credit for unused Basic, and the net amount due. Post-upgrade invoices mirror this breakdown. No manual interventions are required by support; the flow is fully automated. Helpful details: Area of Navexa: Billing > Subscriptions > Plan upgrades Example or screenshot: An anonymized case: Upgrading to Standard attempted during a 30% off Basic term resulted in being charged full list price (e.g., $300) instead of the discounted difference (~$60). Support resolved via refund and a new discounted invoice. Anything else we should know: Handle percentage-based promos and maintain the original promo timeline (e.g., first-year discount) without extending it due to the upgrade. If the promo is no longer eligible at upgrade time, the UI should explain why and present a transparent, non-discounted proration.