The local files on my home PC have a different sized and dated a3.pbo than the one on the server.

Home PC with the first release of the marksman DLC has a

a3.pbo size of 6kb and date of 20/02/2015

The one on the server is
a3.pbo 4kb Date 04/02/2013 date format dd/mm/yy

I use the steam.cmd to update .. so it should be the right one correct ?

Waiting for players to leave so I can test with the local PC version.

Copied the local a3.pbo and bisign to my server.

Now it just kicks the headless client with

15:59:57 Player headlessclient connecting.
15:59:58 Player headlessclient connected (id=HC3520).
15:59:58 Player headlessclient disconnected.
15:59:58 BattlEye Server: Player #3 headlessclient disconnected
15:59:59 BattlEye Server: Player #3 headlessclient (127.0.0.1:2316) connecte

No mention of wrong signature file.

config.cfg contains.

localclient[]={127.0.0.1};
headlessClients[]={127.0.0.1};

checkfiles[] = {};
maxPlayers = 80;
kickDuplicate = 1;
verifySignatures = 2;