OK, here's the complete story: I picked up on Pacifist 4.0 from MacUpdate immediately upon its listing, and I immediately emailed Charles that my original registration info wasn't accepted on his website, and I didn't see anything about an upgrade discount, and was that correct, i.e. is this a full price upgrade with no discount to original owners, or did I miss a link?
His prompt response was a complimentary coupon code...with neither commentary nor clarification.
I responded to that by saying that I appreciated his having supported me, specifically, as a user, not to mention Pacifist in general, for at least 15 years, that I didn't begrudge him the upgrade fee, and that I had just completed a full $20 purchase.
He didn't responded to that, and the next chapter of the story is the email you received...but which I haven't received.
Conclude your own concludings.
Anyway, I've got a complimentary coupon code that I now have no qualms about giving away to the first person who requests it at firstname.lastname@example.org.