The text under this checkbox in advanced setup says: Enable old style urls (ex.: signup.php, profile.php) Usefull only after upgrade from aMember v3 to keep old links working. Does that include affiliate urls too?
Yes this include affiliate urls as well. However affiliate links will not be transferred on upgrade so user will always will be redirected to default redirect url which you have set in aMember CP -> Affiliate Banners and Links