We started our training last night without any problems, than a player gets in with the "infection", yes we tried it unlocked even though we knew it could happen.
Put the msg up that the server would be locked (wednesday and sunday evenings the server is full) if they want to keep playing the needed to get on our TS.
We restarted the server and everybody restarted theire game, locked the server and the server was still full with players, everybody who joined TS was "orderd" to restart the game before joining the game(just to make sure) and we had alot of fun.
Anoying yes, but if it is needed than it is needed to lock a good server, we all respect that we are in Alpha an know this could happen at some point, for us we are just happy to paticipate in the Alpha testing for ARMA3 we enjoy it as it is now and know it will become only better in the near future :)