The A300B4s came from a variety of operators, thus when they were acquired they had different avionics fits (mainly) but some had different freight doors etc (DIB & DIC as was).
EAT/DHL were attempting to get all the aircraft into one of two different avionic fits but the world changed before they were finished and they started 'laying off' aircraft and crews.
As for now, as I understand it, EAT guys are all getting Irish endorsements to fly for ACL, seconded from EAT.
But, watch this space. I can't imagine all the histrionics are over yet. . .