I have a similar system. But I "register" the addresses in a .txt-File first. (sitename-random-number@mydomain) A catchall will flag every mail send to you as s

I have a similar system. But I "register" the addresses in a .txt-File first. (sitename-random-number@mydomain) A catchall will flag every mail send to you as successfully delivered on the spammer site. So the spammer will send again and again, wasting your resources.