trying to figure out the birth year of the Simon Snow Series characters . i hate this! <3
EDIT: here's a way more detailed post on this!!
so far here are my thoughts (keep it in mind that i hate maths and this could be very wrong LOL)
for Simon and Baz, it's done. 21 June and 24 February 1997. Agatha is their age, so 3 October, 1997 1996! (thanks again @ martsonmars)
Penny is probably from 1998, since she's from January and was sent to Watford early. Shepard was 22 in AWTWB/2017, so May 18, 1995.
now, as for the side characters
Lucy must be from around 1975: she was also sent to Watford a year early, probably graduated around 1993, ran off when she was ~20, and was ~22 when Simon was born. "would only be in her 40s" in AWTWB/2017.
Mitali went to her class, so she is probably from around 1973, about 25 years older than Penny. I'd guess Martin is as old as them, and Davy is also about that age. Agatha's mum is about 5 or 6 years older than them, so late 60s (1968 or 1969)
Fiona was also a easy one. She's 37 in 2015/CO, so 1977. This also means she 18/19 when Baz was born, which tracks, because she was in her final year when Natasha was pregnant. Since they're classmates, Ebb is probably also from 1977, as well as Nicodemus (in AWTWB Nico "must be nearly 40")
For Jamie, i'm fairly sure he's from 1978, since around 39 in AWTWB (Lady Ruth showed a picture of his 38th birthday last year)
Now, thanks to this post (bless u @martsonmars) there's a pretty clear timeline for Baz's siblings: Mordelia was born in 2008 (7 in CO/December 2015, 8 in AWTWB/June 2017), Sophie & Petra were born in 2011 (at least 5 ½ in AWTWB, will turn 6 in July-December 2017, were 4 in CO) or 2012 (turned 5 in January-June 2017, were 3 ½ in CO), and Swithin was born around July 2015 (nearly 2 years old in AWTWB, roughly 5/6 months old in CO)
And finally: i feel like Natasha is a tricky one, but probably mid 1960s (EDIT: since apparently rainbow's said she's 9 years older than Lucy, 1965/1966 or something). Malcolm is from around 1963; or at least i think so. apparently he was 46 when Mordelia was born, 8 years before AWTWB, and that would make him ~54 in June 2017. it's also stated that Daphne is still in her 30s, so she's from the 80s (i'd guess early 80s)