For actual data known about what Revolving is, see Revolving under Events. We know that Jame Eagan looks forward to being with his daughter Helena Eagan when his Revolving happens.
Some theories as gathered by the fan community Discord. For Redditors' ideas, see REDDIT LINK.
All prosaic description of said theories the work of this article's author(s):
The Revolving is more like a passing of consciousness/memory/awareness than a passing of the administrative torch. Those two things could be related, ie when one CEO takes over, they accept the consciousness of the previous CEO(s). All CEOs could have Kier's consciousness implanted in them, or else perhaps they are severed and only in one spot, such as the Board Room, they become Kier (innie Kier, outie Jame); the rest of the time they are a normal CEO. Jame Eagan “wept in his bed” which might indicate he is already quite infirm, or perhaps all the CEOs are in some kind of cryogenic suspension chamber thing and their deaths are only for the public. (Though then why would they be reflected in the Perpetuity Wing? A place made for innies)