2.4.5-RC radvd: 4 DNS Servers one too many in DHCPv6 Options

[mikahe]

I just noticed this oddity when adding two more DNS servers here:

Services/DHCPv6 Server & RA/<interface>/DHCPv6 Server
DHCPv6 Options:
DNS Servers: 0..3 IPv6 addresses ok

• When 4 IPv6 addresses entered, radvd does not start

Router Advertisements:
Route mode: Assisted RA Flags
DNS Configuration:

Use same settings as DHCPv6 server

[mikahe]

I'm currently on 2.4.5-RC (amd64) built on Sat Feb 08 13:43:43 EST 2020
These entries might be related in System General Log:
/services_dhcpv6.php: The command '/usr/local/sbin/radvd -p /var/run/radvd.pid -C /var/etc/radvd.conf -m syslog' returned exit code '1', the output was ''

[mikahe]

diff radvd.conf radvd_ng.conf 
59c59
< 	RDNSS 2620:fe::fe 2620:fe::9 2a00:1098:2c::1 { };
---
> 	RDNSS 2620:fe::fe 2620:fe::9 2a00:1098:2c::1 2a00:1098:2b::1 { };