DHCPv6 relay mode stopped work between snapshot 18th Aug and 21st Aug

I am working on some customization for sunxi target
I used a build form LEDE website on 18th Aug and DHCPv6 was working correctly
Then I have built a LEDE firmware yesterday 21st Aug, it is working ok excpet that DHCPv6 does not work correctly
First I see only one instance of odhcp running (shouldn't be 2?)
I have two dumb LEDE AP with a LAN6 DHCPv6 set. One get a SLAAC address and I can ping the IPv6 sites, the other (same LEDE 17.01.2) get the prefix64::1 address (!!!!) and cannot ping. Another Linux server just does not get any IPv6 address from the 64 network, only local link....
I see that odhcpd version is now: 2017-08-16-94e65ee0-1
Honestly I don't remember if on the snapshot of 18th Aug it was different
Anyone with the same problem?