Cannot change credit card without canceling Nitro subscription

I need to move my Nitro subscription to a different credit card. I don't want to cancel and re-subscribe because I would lose the "subscriber since" date in my profile, and I do not want to lose credit for the remaining days of the subscription period. However, Discord support said there is no way to update the credit card without canceling the active subscription. Please, would you build a way to update the credit card on the active subscription without canceling it?