This is only one reason that some beleive that the Columbia Union is NOT in rebellion against the GC. It is doing what it is allowed to do. I have posted earlier other reasons why I believe that the Union is doing what it is allowed to do under its Constitution. I will not repeat those here.
It seems to me that you are arguing as if you are on the side of John Harvey Kellogg, who changed the charter of the Battle Creek San and, with the help of lawyers, used legalities to steal the San away from the denomination. To a worldly minded lawyer, it might not be theft, but it certainly was.
All legalities aside, we still have Acts 15, Ellen White's comments about Acts 15, and 9T 260-261, a matter you haven't addressed at all, except to refuse to address it.
Let's be clear: A Union is not permitted by God under its Constitution to violate Acts 15 and 9T 260-261. There is no theological basis for saying that God permits any such thing.
You may want to frame the discussion in only human, worldly terms, and you may not want to frame the issues in a spiritual context, but that seems rather strange.
Now if we do venture onto that ground and discuss it only from purely human, worldly terms, does not the GC and NAD
Working Policies mandate that all union officers be in harmony with church policies? Is not one of those church policies that GC Sessions are the highest authority on earth under God? Does not another of those policies state that officers who won't abide by these policies should not be re-elected by their constituencies? On what basis, then, can anyone suggest that the Columbia Union is not rebelling against GC Session votes?