[Dovecot] adding servers to director_mail_servers

[Cor Bosman]

Is there a specific order in which one has to add servers to director_mail_servers, Let's say I have 20 loadbalanced director servers (I dont, but for arguments sake). I want to add 5 servers to director_mail_servers.  If I do this by restarting each director server 1 by 1 with an updated conf, it seems the 5 new servers dont get added. Or at least I dont get what makes it work eventually. Only after restarting a few times they seem to all want to agree on the new list of servers. 

Cor