Always_bcc with aliases

[Prince Law Offices]

My postfix server receives email for several sub-domains of my-domain.  All 
email addressed to one of the sub-domains is aliased to u...@my-domain.com 
<mailto:u...@my-domain.com>.  For example:

        a...@sub-domain1.my-domain.com   
<mailto:a...@sub-domain1.my-domain.com>=> u...@my-domain.com 
<mailto:u...@my-domain.com>
        d...@sub-domain1.my-domain.com <mailto:d...@sub-domain1.my-domain.com>  
 <mailto:a...@sub-domain1.my-domain.com>=> u...@my-domain.com 
<mailto:u...@my-domain.com>
        g...@sub-domain2.my-domain.com <mailto:g...@sub-domain2.my-domain.com>  
 <mailto:a...@sub-domain1.my-domain.com>=> u...@my-domain.com 
<mailto:u...@my-domain.com>
        1...@sub-domain3.my-domain.com <mailto:1...@sub-domain3.my-domain.com>  
 <mailto:a...@sub-domain1.my-domain.com>=> u...@my-domain.com 
<mailto:u...@my-domain.com>

I use transport to pipe the email to an external application:

        u...@my-domain.com <mailto:u...@my-domain.com>  etof:

I would also like to archive a copy of every email, so I use an always_bcc

        always_bcc = arch...@my-domain.com <mailto:arch...@my-domain.com>


But this doesn’t work “anymore.”  I believe it used to work, but it’s possible 
I didn’t test properly in the past.  I realize that “BCC recipients are not 
generated after Postfix forwards mail internally”  Is the use of the alias 
and/or the transport considered an internal forward?

If it is an internal forward, does anyone have any suggestions other than my 
external application re-sending the email?