[bitfolk] Postfix, bcc_senders_maps, and SRS

For many years, I've used Postfix's ability to automatically BCC mail that is being sent through it to generate an archive of sent mail. Unfortunately, the 'use bcc_senders_maps to have a file with a list of accounts to do this to' method no longer works if you have to have SRS enabled and your outgoing emails appear to come from one domain, that of the server, to avoid having to set up DKIM and SPF dozens and dozens of times. Before: The 'received from' and the 'return path' headers were both the domain that was the 'from' domain. After: The 'received from' details are stripped and replaced by something like Received: from [127.0.0.1] (localhost/[127.0.0.1]) by (server) (Postfix) with ESMTPSA id 514CD810AC SRS makes the return path Return-Path: <SRS0=qeUa65BM=5O=('from' domain)=('from' sender)(a)srs.(server)&gt; Something in that breaks the bcc_senders_maps functionality. Before I could automatically archive outgoing email from some domains and not others, and treat each individually, but now iit appears to be all or nothing, and every senders domain is the same: srs.(server). What other ways are there of getting an automatic bcc of a subset of everything sent through the server? One thought is to make the receiving address filter it - mail from A gets sent on to its real archive, mail from B gets sent on to its real archive, mail from C and D gets deleted - but that's a bodge. Ian