If you are in hurry, you have to pay someone to help you or help you yourself.Sure its free, but realize that we use pkgs for production and that is a very big challenge when you are stuck with low system and building ports takes ages to complete. Free or not this is critical issue for all.
But as far I know sometimes searching for root issue is bit more quest for an achievement
The hack that SaMaeL posted seems merely efficient. He just forgot to say that the
ALTABI
thing must be added in /usr/local/etc/pkg.conf: ALTABI = "FreeBSD:12.0:amd64"