UPDATE 2.25PM UK: Ubisoft has now formally acknowledged Assassin's Creed Infinity and detailed more of how it will be run, and who will work on it.
The lengthy blog post contains mention of two teams led by two creative directors. Clint Hocking, formerly of Splinter Cell and Watch Dogs Legion, will lead a team at Ubisoft Montreal. Jonathan Dumont, a veteran of Assassin's Creed Syndicate and Odyssey, will lead a team at Ubisoft Quebec.
The Infinity project that will include the games made by both these teams will be led by Marc-Alexis Côté, who will now serve as executive producer of the entire Assassin's Creed franchise. Côté worked on Brotherhood before becoming creative director on Syndicate, and is one of the most senior staff at Ubisoft Quebec.