Why is EPG (SEPG earlier) missing from CMMI-Dev, V 1.2?

I don't find the term Engineering Process Group or acronym EPG in the CMMI. The OPF PA where EPG was defined earlier has the reference of 'process group' in GP 2.4 and elsewhere. Is there any specific reason for which the word 'engineering' was elminated from the model?
I don’t think the EPG or SEPG for that matter was ever referenced in the CMMI. Though I could be wrong. I just checked the v1.1 book and it doesn’t mention the EPG or SEPG in OPF GP 2.4. In point of fact, there is no difference in OPF GP 2.4 between v1.1 and v1.2. You are correct in referencing GP 2.4 because that is the GP that expects a group such as the EPG or SEPG to be assigned responsibility for OPF. However, the reason the CMMI does not mention these two groups is because you don’t need a group named the EPG or SEPG to perform the OPF activities. You can call the group whatever name you choose, you just need to assign the OPF responsibilities to someone or some group. And a group can be one person.