In case you missed it earlier,

The Book of PF, 4th Edition: It's Here, It's Real https://nxdomain.no/~peter/its_real_its_here.html

And I will have copies with me to upcoming events #openbsd #freebsd #bsd #pf #packetfilter #bookofpf #4thedition #asiabsdcon #bsdcan #eurobsdcon @nostarch