Link on return page - is it possible?

So I had a site working nicely with the Framework. It’s simple: no registration, just returning a Specific Page private link to the customer after PayPal payment.
Then I upped to Pro so I could generate a secure link and add it to the paypal return page.

What I’m wondering now is whether (instead of the link) I could just redirect the customer to the private page. I can obviously redirect them to a public page using the ‘success’ url, but I can’t make it work for a private page.

Does anyone know different?

many thanks!