I've always felt that they'd announce it in December right before The Game Awards and then release in May or June. I still expect an announcement before the end of the calendar year, otherwise I feel like they'd have been better off not saying anything just yet. Switch 1 had its initial reveal trailer in October and released in March. A Switch 2 initial reveal trailer in December with a release in May or June is roughly the same length of time (and presumably the Switch 2 will be basically Switch but more powerful, so less explaining will hopefully need to be done).