Sorry for the late answer, got to catch up with life….
Here is the ifconfig.txt with the ipv6_link_local selected on network interface and unbound failing to start on reboot.
igb0: flags=8843 <up,broadcast,running,simplex,multicast>metric 0 mtu 1500
options=400bb <rxcsum,txcsum,vlan_mtu,vlan_hwtagging,jumbo_mtu,vlan_hwcsum,vlan_hwtso>ether 0c:c4:7a:31:aa:08
inet6 fe80::ec4:7aff:fe31:aa08%igb0 prefixlen 64 scopeid 0x1
inet 71.48.1.43 netmask 0xfffff800 broadcast 71.48.7.255
nd6 options=21 <performnud,auto_linklocal>media: Ethernet autoselect (1000baseT <full-duplex>)
status: active
igb1: flags=8843 <up,broadcast,running,simplex,multicast>metric 0 mtu 1500
options=400bb <rxcsum,txcsum,vlan_mtu,vlan_hwtagging,jumbo_mtu,vlan_hwcsum,vlan_hwtso>ether 0c:c4:7a:31:aa:09
inet 192.168.100.250 netmask 0xffffff00 broadcast 192.168.100.255
inet6 fe80::1:1%igb1 prefixlen 64 scopeid 0x2
inet6 2602:47:3001:2b00::1 prefixlen 64
nd6 options=21 <performnud,auto_linklocal>media: Ethernet autoselect
status: no carrier
igb2: flags=8843 <up,broadcast,running,simplex,multicast>metric 0 mtu 1500
options=400bb <rxcsum,txcsum,vlan_mtu,vlan_hwtagging,jumbo_mtu,vlan_hwcsum,vlan_hwtso>ether 0c:c4:7a:31:aa:0a
inet6 fe80::ec4:7aff:fe31:aa0a%igb2 prefixlen 64 scopeid 0x3
inet 71.48.1.75 netmask 0xfffff800 broadcast 71.48.7.255
nd6 options=21 <performnud,auto_linklocal>media: Ethernet autoselect (1000baseT <full-duplex>)
status: active
igb3: flags=8c02 <broadcast,oactive,simplex,multicast>metric 0 mtu 1500
options=403bb <rxcsum,txcsum,vlan_mtu,vlan_hwtagging,jumbo_mtu,vlan_hwcsum,tso4,tso6,vlan_hwtso>ether 0c:c4:7a:31:aa:0b
nd6 options=21 <performnud,auto_linklocal>media: Ethernet autoselect
status: no carrier
pflog0: flags=0<> metric 0 mtu 33160
pfsync0: flags=0<> metric 0 mtu 1500
syncpeer: 0.0.0.0 maxupd: 128 defer: off
syncok: 1
enc0: flags=0<> metric 0 mtu 1536
nd6 options=21 <performnud,auto_linklocal>lo0: flags=8049 <up,loopback,running,multicast>metric 0 mtu 16384
options=600003 <rxcsum,txcsum,rxcsum_ipv6,txcsum_ipv6>inet 127.0.0.1 netmask 0xff000000
inet6 ::1 prefixlen 128
inet6 fe80::1%lo0 prefixlen 64 scopeid 0x8
nd6 options=21 <performnud,auto_linklocal>wan_stf: flags=4041 <up,running,link2>metric 0 mtu 1280
inet6 2602:47:3001:2b00:: prefixlen 24
nd6 options=1 <performnud>v4net 71.48.1.43/32 -> tv4br 205.171.2.64
igb0: flags=8843 <up,broadcast,running,simplex,multicast>metric 0 mtu 1500
options=400bb <rxcsum,txcsum,vlan_mtu,vlan_hwtagging,jumbo_mtu,vlan_hwcsum,vlan_hwtso>ether 0c:c4:7a:31:aa:08
inet6 fe80::ec4:7aff:fe31:aa08%igb0 prefixlen 64 scopeid 0x1
inet 71.48.1.43 netmask 0xfffff800 broadcast 71.48.7.255
nd6 options=21 <performnud,auto_linklocal>media: Ethernet autoselect (1000baseT <full-duplex>)
status: active
igb1: flags=8843 <up,broadcast,running,simplex,multicast>metric 0 mtu 1500
options=400bb <rxcsum,txcsum,vlan_mtu,vlan_hwtagging,jumbo_mtu,vlan_hwcsum,vlan_hwtso>ether 0c:c4:7a:31:aa:09
inet 192.168.100.250 netmask 0xffffff00 broadcast 192.168.100.255
inet6 fe80::1:1%igb1 prefixlen 64 scopeid 0x2
inet6 2602:47:3001:2b00::1 prefixlen 64
nd6 options=21 <performnud,auto_linklocal>media: Ethernet autoselect (1000baseT <full-duplex>)
status: active
igb2: flags=8843 <up,broadcast,running,simplex,multicast>metric 0 mtu 1500
options=400bb <rxcsum,txcsum,vlan_mtu,vlan_hwtagging,jumbo_mtu,vlan_hwcsum,vlan_hwtso>ether 0c:c4:7a:31:aa:0a
inet6 fe80::ec4:7aff:fe31:aa0a%igb2 prefixlen 64 scopeid 0x3
inet 71.48.1.75 netmask 0xfffff800 broadcast 71.48.7.255
nd6 options=21 <performnud,auto_linklocal>media: Ethernet autoselect (1000baseT <full-duplex>)
status: active
igb3: flags=8c02 <broadcast,oactive,simplex,multicast>metric 0 mtu 1500
options=403bb <rxcsum,txcsum,vlan_mtu,vlan_hwtagging,jumbo_mtu,vlan_hwcsum,tso4,tso6,vlan_hwtso>ether 0c:c4:7a:31:aa:0b
nd6 options=21 <performnud,auto_linklocal>media: Ethernet autoselect
status: no carrier
pflog0: flags=100 <promisc>metric 0 mtu 33160
pfsync0: flags=0<> metric 0 mtu 1500
syncpeer: 224.0.0.240 maxupd: 128 defer: on
syncok: 1
enc0: flags=0<> metric 0 mtu 1536
nd6 options=21 <performnud,auto_linklocal>lo0: flags=8049 <up,loopback,running,multicast>metric 0 mtu 16384
options=600003 <rxcsum,txcsum,rxcsum_ipv6,txcsum_ipv6>inet 127.0.0.1 netmask 0xff000000
inet6 ::1 prefixlen 128
inet6 fe80::1%lo0 prefixlen 64 scopeid 0x8
nd6 options=21 <performnud,auto_linklocal>wan_stf: flags=4041 <up,running,link2>metric 0 mtu 1280
inet6 2602:47:3001:2b00:: prefixlen 24
nd6 options=1 <performnud>v4net 71.48.1.43/32 -> tv4br 205.171.2.64
ovpns1: flags=8051 <up,pointopoint,running,multicast>metric 0 mtu 1500
options=80000 <linkstate>inet6 fe80::ec4:7aff:fe31:aa08%ovpns1 prefixlen 64 scopeid 0xa
inet 192.168.110.1 --> 192.168.110.2 netmask 0xffffff00
nd6 options=21 <performnud,auto_linklocal>Opened by PID 35006
ovpns2: flags=8051 <up,pointopoint,running,multicast>metric 0 mtu 1500
options=80000 <linkstate>inet6 fe80::ec4:7aff:fe31:aa08%ovpns2 prefixlen 64 scopeid 0xb
inet 192.168.120.1 --> 192.168.120.2 netmask 0xffffffff
nd6 options=21 <performnud,auto_linklocal>Opened by PID 37481
ovpnc3: flags=8051 <up,pointopoint,running,multicast>metric 0 mtu 1500
options=80000 <linkstate>inet6 fe80::ec4:7aff:fe31:aa08%ovpnc3 prefixlen 64 scopeid 0xc
nd6 options=21 <performnud,auto_linklocal></performnud,auto_linklocal></linkstate></up,pointopoint,running,multicast></performnud,auto_linklocal></linkstate></up,pointopoint,running,multicast></performnud,auto_linklocal></linkstate></up,pointopoint,running,multicast></performnud></up,running,link2></performnud,auto_linklocal></rxcsum,txcsum,rxcsum_ipv6,txcsum_ipv6></up,loopback,running,multicast></performnud,auto_linklocal></promisc></performnud,auto_linklocal></rxcsum,txcsum,vlan_mtu,vlan_hwtagging,jumbo_mtu,vlan_hwcsum,tso4,tso6,vlan_hwtso></broadcast,oactive,simplex,multicast></full-duplex></performnud,auto_linklocal></rxcsum,txcsum,vlan_mtu,vlan_hwtagging,jumbo_mtu,vlan_hwcsum,vlan_hwtso></up,broadcast,running,simplex,multicast></full-duplex></performnud,auto_linklocal></rxcsum,txcsum,vlan_mtu,vlan_hwtagging,jumbo_mtu,vlan_hwcsum,vlan_hwtso></up,broadcast,running,simplex,multicast></full-duplex></performnud,auto_linklocal></rxcsum,txcsum,vlan_mtu,vlan_hwtagging,jumbo_mtu,vlan_hwcsum,vlan_hwtso></up,broadcast,running,simplex,multicast></performnud></up,running,link2></performnud,auto_linklocal></rxcsum,txcsum,rxcsum_ipv6,txcsum_ipv6></up,loopback,running,multicast></performnud,auto_linklocal></performnud,auto_linklocal></rxcsum,txcsum,vlan_mtu,vlan_hwtagging,jumbo_mtu,vlan_hwcsum,tso4,tso6,vlan_hwtso></broadcast,oactive,simplex,multicast></full-duplex></performnud,auto_linklocal></rxcsum,txcsum,vlan_mtu,vlan_hwtagging,jumbo_mtu,vlan_hwcsum,vlan_hwtso></up,broadcast,running,simplex,multicast></performnud,auto_linklocal></rxcsum,txcsum,vlan_mtu,vlan_hwtagging,jumbo_mtu,vlan_hwcsum,vlan_hwtso></up,broadcast,running,simplex,multicast></full-duplex></performnud,auto_linklocal></rxcsum,txcsum,vlan_mtu,vlan_hwtagging,jumbo_mtu,vlan_hwcsum,vlan_hwtso></up,broadcast,running,simplex,multicast>
system.log shows an error that unbound could not start because cannot bind socket: can't assign requested address for fe80:…..