Native ipv6 and getting rid of the "wan6" interfaces? What is our best practice?

Environment: github master (OpenWrt SNAPSHOT, r7337-3ce1158)

In this day and age, do we still need to have a fake wan6 interface in addition to our wan interface for IPv6 when running DHCP prefix discovery, or is there a better way to configure this? I realize this was a kludge we originally did because we were using udhcpc on the v4 interface and odhcp6c on the v6 interface, however...

I'm dual homed. I'm using mwan3, and while I -do- have it finally working, I'm getting warning messages because of the cloned nature of the whole shebang.

Is there any reason in 2018 that we're still doing interface aliases to run ipv6 for the most basic configuration of a dual-stack router to an ISP (or two)? Can we merge the configuration through some magic I have missed so that we're either supporting dhcpv6 in udhcpc (it does) or dhcpv4 in odhcpv6c (it does).

This is my current configuration snippet:

config interface 'wan_cc'
        option ifname 'eth0.10'
        option proto 'dhcp'
        option metric '120'

config interface 'wan_cc6'
        option ifname '@wan_cc'
        option proto 'dhcpv6'
        option reqaddress 'try'
        option metric '120'
        option reqprefix '60'

config interface 'wan_mb'
        option ifname 'eth0.11'
        option proto 'dhcp'
        option metric '110'

config interface 'wan_mb6'
        option ifname '@wan_mb'
        option proto 'dhcpv6'
        option reqaddress 'try'
        option metric '110'
        option reqprefix 'auto'

Do you get the same issues if you use the real interface names as ifname, eth0.10 and eth0.11?

https://wiki.openwrt.org/doc/uci/network#aliasesthe_new_way