My first experience with this new process this past Sunday:

• ICN-DFW (ticketed in Business): Boarding pass says "Group BC" GA starts boarding with CKs. Then calls "Group 1" Then calls "Group 1 and families with children under 2", then calls "Group 2". I didn't hear the rest, because I'd boarded. But I did see at least two people standing around with business class BPs, waiting for "Group BC" to be called.
• DFW-DEN (ticket in F): GA starts with "CKs and First Class" that's all I heard.

Clearly some kinks to be worked out here...