Ahoi! How has this topic developed in the time since April of last year? I spotted the dreaded HAS_X_OUTGOING_SPAM_STAT in my mail tester check today, and after some research, I guess I am suffering from the same problem with my cpanel mail server.
From what I am seeing on my end, this was fixed in 94 and 96, so I would not expect the same issue to be happening at this time. In the changelog we show the header option was removed: