In WatchGuard XTM SMTP Proxy definitions, it implies you can set up a rule for "masquerading". However, how do you set up the replacement string? For instance, if I want firstname.lastname@example.org to be redirected to email@example.com, it is easy enough to match the string and replace it. But, if I want everyone @contoso.com to be redirected to their same name @contoso.org, how do you set up the replacement string? You can use a wildcard on the string match but what syntax do they use for the replacement string to attach the portion before @contoso.com. Seems that this should be a simple process for creating masquerading.