So Debian 12 (bookworm) is releasing on Saturday, 10th June. I.e. the day after tomorrow. I had completely lost track and only heard about this because Debian India sent out an email about a release party. Or parties.
I see that Debian has managed to keep a 2 year interval, more or less, between releases since the Debian 2.2 (potato) release in August 2000.
Actually, there was a 3 year gap between Debian 3.0 (woody) and Debian 3.1 (sarge). So perhaps it would be more accurate to say that Debian has managed a 2 year interval from Debian 3.1, released on 6th June 2005.