Who even needs generations? Abolish the concept completely from LGPE forward, in my opinion. The less Game Freak restrict theemselves creatively and thematically to compartmentalizing changes by system or region, the better, and the less fans should try to box them in. The Switch could be the series’ home for the better part of a decade, and it would be better off as a period of total innovation and change.
Anyway, these next titles are absolutely not getting revealed as early as January - that would be the longest lead time between announcement and release, tied with X and Y, and leaves almost too little time to properly promote the games that just got released mid-November. Games which, mind you, are already selling well. They’ve never moved on to announcing a new game in just two months; even B2W2, with the old staggered release system, still had three months of availability in most areas before X and Y were announced, and half a year in Japan.
I could see February at a push, but I’m betting on later, and as late as May depending on how LGPE do commercially.