What such CCG?

That is an Armstrong splinter group. Just click on the "English" icon, and right away, all of the key doctrines jump out: Anglo-Israelism; sabbatarianism, etc.
Beginning in the 70's scandals, not only did Garner Ted break off of the WCG and formed his CGI ("...International"), but several other groups as well; all claiming to be the sucsessor to the true Church, with names to reflect this: Biblcal Church of God; Christian Church of God; Christian Biblical Church of God, etc. The final straw being the WCG's defection toward orthodoxy, when we saw the Global Church of God and a whole new batch of others.
Thus they are similar to Campbellism, in their claim to being the true Church, and the history they use to justify it (tracing through the Anabaptists, Waldensians, Albigenses, etc). They do however have more of a point that "Church of God" is used [12×] more than "Church of Christ" (once).
Their attitude toward Baptists is the same: they are "deceived" but "sincere", not-yet-"called" people in the world like everyone else, who follow the [future] antichrist's Sunday worship.

 

With all these Armstrong Splinter groups there is a command that Christians must keep the feasts of the Old Testament, if you say to them that Paul teaches in Scripture that Gentiles are not required to follow the Jewish law, they will tell you that these laws are for everyone not just the Jews, despite what you point out to them in Scripture they are bound in Legalism that Paul tried to prevent.

What is interesting is that if they are so perfect, why the high number of splits with others that have similar beliefs to them, they all compete with each other and say that the other groups are in error and push there own magazines and radio programmes over another. What it shows me is that they each want to have there own monopoly on power over people.

I would have a look at articles on the "Let Us Reason" site that look at there error's in some details and have testimony of ex members that have left them.

I might add that one of the reasons that the WCG did eventually adopt a Trinitarian Position, was that a number of there members went to a Evangelical Bible College and came out convinced of our standard Baptist doctrine after studying all the documents for themselves. Hence why these splinter groups try very hard to keep there members out of Bible College and try to control what they read and get tapes of in relation to Christianity.

 

It's plain and simple (as I call it): "one-upmanship". Armstrong was all about authoritarianism anyway, with doses of big business mentality thrown in (one reason I stayed out of the group, back when I thought some of their doctrines were true), and this bred envy and competitiveness. So at the first sign of trouble, ministers were eager to break off, and become the "Pastor General" (Armstrong's title) of their own "true flock", while denouncing the parent group as fallen. It seems Armstrong's eschatology even left a hole open for this, as even though he claimed he was the final apostle, and Christ would come back at any time (they used to set dates, such as 1975 as well, just like the JW's), he claimed he was the messenger of the "Philadelphia era", rather than Laodicea, which was really the last of the churches. Of course, this would allow him to say his era was the "faithful" one, rather than the fallen and lukewarm one, but when the groups broke off; especially after the parent group turned away from the doctrines, they could now claim that the WCG did in fact finally enter the "Laodicean era". Now, splinters of the splinter groups claim WCG is out of the picture of being the "Church", and call each other the Laodiceans. Go figure! :roll:

Of course, the whole argument from Armstrong on down, is that the Sabbath is the "true sign" of God, yet they all keep it, yet still reject each other. So it must not be the true sign. Jesus said the true sign was "if you have love for one another" (John 13:35). They've all missed it; "desiring to be teachers of the Law".

As for the Trinity, what I've always heard from them was that it was their Greek scholars (actually Greek members from their Church in Greece themselves), who began questioning their exegesis of several scriptures. Then they began accepting "three hypostasis", but insisted on saying it that way. Also, I think it was CRI, commenting on the change, who said it was their retracting their position on the Law that led them to a chain of rethinking ultimately leading to them accepting the Trinity.