IEC 62424 Ed. 2.0 (including CAEX 3.0) was developed with intensive coorperation of the AutomationML association. CAEX 3.0 is the technical basis for te upcoming AutomationML version 2.10 (IEC 62714-1 Ed. 2.0). Upwards compatibility between the upcoming version and the current AutomationML version 2.0 (IEC 62714-1 Ed. 1.0) is guaranteed. The software libraries, which are provided by the AutomationML association, will support and convert both versions seamlessly.
You can download the 2nd edition of IEC 62424 here.