If you have a Common thank-you page URL entered in Seller Admin > Account Preferences, that overrides all other thank-you/redirection page settings you may have assigned elsewhere.
Also, if you are using product-specific Redirection URLs, we will only allow the Redirection after Checkout if the payment processor has confirmed completion of payment; if the buyer finishes Checkout and continues before the actual payment process is complete, they may see our generic thank-you page instructing them to check their email for further details about claiming their purchase. Once the processor confirms completion of payment, we would issue the buyer a thank-you email with a link to our thank-you/download page, which would insta-redirect to your URL if you had one configured for that product.
