https://forum.opnsense.org/index.php?topic=20978.msg106200#msg106200
This is the code Jason Donenfeld and FreeBSD core developers have been working on.
It’s the code that Netgate sponsored, Jason found flaws in and then imported over and started fixing. So it’s now a fork of what Netgate has in their current system but that will be removed in the upcoming update. Also, Netgate has not clarified when or if it will be back in the pfsense kernel.