Just to add, we have a work-around for now… basically, we had to add some parameters to the redirectUrl, then create the association between the user ID and the subscription ID, then redirect them onto the manage page for the subscription.
It’s not idea to do it this way, since if any part of this front-end process fails, we’ll end up with a person getting subscribed, but their user ID not getting associated with their subscription which would be an issue for us to deal with on the customer service side of things… something we’d obviously like to avoid 