I do not accept (and never have accepted) wildcards. I create a new alias in advance every time. I use the ISP's server for sending, and use my own server for

I do not accept (and never have accepted) wildcards. I create a new alias in advance every time. I use the ISP's server for sending, and use my own server for receiving (the menu for install Exim has a "smart host" option which does this).