sender maps and whitelisting

[Damian]

> Yes, that's correct - I've always used postfix always_bcc and didn't realize there was one for amavis as well.

If you want to keep it that way, you could declare bcc-user a spam_lover:

> @spam_lovers_maps = ([                                                                                                                           
>   'bcc-user at gambit.example.com',
> ]);


> It would also be very helpful to have a better description of the syntax I needed to use here for wildcards.
> 
> What's the difference between the new_RE() form and the hash-type lookup table? How do regular expressions work for the hash table 
> to match an entire domain, for example?

The hash-type lookup is not a regex lookup. See [1].

[1] https://gitlab.com/amavis/amavis/-/blob/v2.13.1/README_FILES/README.lookups#L114-124