officially no. (not that i know of, unless someone in HR can confirm)

but within the same community, the bosses will choose who to groom based on their perceived performance. degree class is not an so impt factor once you enter the service(unless you are scholar). they 'assign' a CEP for them to gauge their end point and groom them towards that position for the long term. example, in that community, if the highest DXO post is a DX15, they will need to identify potential people to eventually take over in 15-20 years. its hard to hire off the street if the job is specialised to mindef operations.

also, DXOs are empowered to job hop within mindef and take a higher position. hence no CEP for DXO as it doesnt make much sense. Some can jump from DX10 to DX12 directly only after 8 years in service and only barely pushing mid-30s. most DXOs will end at DX12, so either he/she is the chosen one, or he/she is lucky with the time and space.