samba - May 2016 - Domain guest users broken after upgrade to 4.3.9

Hello,

I'm using < domain guest > users since a long time for guest users.
Since I upgraded DC to last 4.3.9 release (yesterday), users with < domain
guests > as principal group can't access anymore to sysvol or netlogon,
no GPO is applied.
I thinking about downgrading my 20 DC :(
Best regards