How to Update Credit Card Info
PayPal users: First, if you paid via PayPal, would update their credit card info inside their PayPal account at paypal.com.
Other credit card users: Those who paid via Stripe (e.g., not PayPal) can update your subscriptions on your billing settings page (Login > Account Menu > Billing Settings Submenu). Here's the direct link: https://backpackinglight.com/account/billing-settings/
If you purchased a single-payment product (like a course), the option to update credit card information is unneeded and does not display. If you purchased a subscription, then on your billing page, a Recurring Subscription Orders area will display where you can click "update billing details" and complete the process of updating your credit card information:
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Note: if there is not an option to update billing details on your billing settings page, you either paid via PayPal and would update your info there, or you did not purchase a subscription and therefore do not have a reason to update your credit card info.