The beginning of 17776 really is so interesting in the way that it sets up the rest of the story. The calendar backdrop was such a stroke of genius, because it forces the reader to focus on nothing but the passage of time and nine's increasing desperation and loneliness. and then when ten responds with 'i love you so much'--well, i still had no idea who these characters were, but i was already invested enough in them to feel anxious scrolling through the days where they weren't able to make contact with each other. and then, when ten tells nine not to contact them for 27 years, my first thought was, 'but that's a life! that's a life apart for two people who clearly care about each other'
and then the scroll through the days, once again forced to focus on nothing but the passage of time, leading straight into the reveal that these people aren't actual people with a lifespan of a century or less, and THEN the reveal that even humans aren't people with a lifespan of a century or less anymore, and the way that the reader has been interacting with the passage of time is so FUNDAMENTALLY different to how it works for the current denizens of the earth
just, what a great way to really bring out the focus of the story right from the beginning: how would we change, if the constraints and anxieties of finite time were lifted from us as a species?