I was trying to get my Meraki AP on IPv6. It seems the AP does not support DHCPv6 (and will not any time soon I have been told on forum) Android devices also do not support DHCPv6 and rely on RDNDSS.
Windows 10 will only use RDNSS if there is no DHCPv6 or DHCPv4 server. To get RDNSS to work on windows 10 need to disable DHCP IPv4 and DHCP IPv6. So for the best compatibility in a dual stacked environment you need to have DHCPv4 and DHCPv6 add RDNSS for segments with android and Meraki devices.
I thought DNS option were only supported on DHCPv6 but they supported on RDNSS rfc8106
This allows RA DNS options to distribute DNS server information as part of RA advertisements.
ip address x.x.x.x 255.255.255.0
ipv6 address 1::1:0:0:0:1/64
ipv6 nd other-config-flag
ipv6 nd ra dns server 2001:8000:101::1
ipv6 nd ra dns server 2001:8000:101::2