The Gang of Time is a secret Chinese cabal that is involved in many international businesses, particularly in the area of real estate and finance.
The leader of the cult is an ageless, active young man, Qi Jing Li. Though, due to the nature of this cult, the past is a constantly shifting thing, it could be said that Li came upon a series of books called "The Epilogues of Tsun Dng"sometime within the last 300 years. He studied these books, and began to meddle in the time around his village. There is some evidence that this was in the Nineteenth century, though now the machinations of Qi Jing Li can reliably be traced to the very beginnings of Chinese Civilization.
As he grew in the dark knowledge that these tomes exposed him too, he created/found an eddy in time, sort of a timeless eye of the temporal hurricane, that was inhabited by the Kec'tosot'Soet, which he subdued and made his home there. Now, the cult is actually "headquartered" (for lack of a better term) on a parallel wave of probability collapse, created and propagated by their ancient and not-quite-understood technology. From this space outside of space, they can reach in and tinker in small ways to set things the way they need to be set. When needed, they can step in and act personally. They aren't really sure how they do this, but meditating upon the properly inscribed multi-dimensional insignia on their rings allows them to gate back and forth.
Qi Jing Li began to gather men around him who wanted to share in the fortune that his magic could bring. Though they come from many different ages, they are mostly Chinese, though not exclusively so. They have read some or all of the Epilogues, depending on how long they have been involved in the Gang, and their personal temperament and interests. The highest members of the cult have certainly read most or all of the texts. They are aware of Yah'kwi'aa, and seek to use his temporal nature to undo the existence of man, which is necessary to bring about the end times. They use their business connections to look for the type of events that shows a visitation of Yau. When they find an incident of Yau, they see if it is predicted in one of their books (There are others besides the Epilogues; some of them are alternate Epilogues), and then they move in, and try to control it. These events usually have some focus- and it could be focused on anything, a place, an event, a developing idea; one current one is focused on the Swisher bloodline.
Often the first members of the cult on the scene of one of these temporal junctions have less apocalyptic goals; maybe they are just trying to use the temporal events to move up in the cult. Only a few at the top really know and desire to unmake humanity. The Gang of Time has many resources, but often these resources are bound up in the business structures that keep them. They have such a long view of time that they are incapable of not planning for it, even though they are also trying to end the world. Their use of timesculpting is not absolute; timesculpting is a delicate and dangerous art, and many structures of time, carefully constructed, will collapse due to unseen flaws in the original stone. The skill and knowledge of each practitioner is different, as well, and no one, not even Li, has anything like a complete knowledge of time- this is the exclusive domain of Yog-Sothoth.
The Gang of Time has many holdings in all of the major financial centers, as well as means of production everywhere.
They have as their symbol the Chinese ideogram of time. But there are a bunch of these, from different eras and dialects, each having different shades of meaning. Their true symbol is a multidimensional glyph that incorporates all of them. When it is properly written- as it is on the rings- it slowly (usually) changes from one form to another. Wise men can interpret things from this, as the time it describes is the type of time at the moment- the temporal weather, so to speak. I don't think that they have complete knowledge of the Yau cycle, and will probably confuse servitors, and associated monsters, with each other, etc.