timeline

since a lot of people in the comments seemed confused (and i also just wanted to compile this info) here’s a ROUGH timeline/chapter overview (buckle up):

ch1-50: adults (xixi is in uni, but the year is unknown; boys are 18+ as they talk abt going out drinking and xixi has beer in his fridge; tianshan don’t appear here)
*ch45 explains that jianyi disappeared on the second day of high school but came back recently while xixi is in uni (so he was gone at least 3 years)

ch51- 445: 3rd year middle school main story (boys are 14-15yo; u can usually tell the timeline from their school uniforms, which they sometimes wear outside too)
*ch348/405/432: hetian’s school transfer is mentioned, but he refuses to go / hetian says he’ll do what’s needed in exchange for hecheng’s help (implying he’ll accept the transfer) / hecheng says it’s time to leave, but hetian wants to say goodbye
*ch224+271+313+378+412: adults - hetian returns on christmas (jianyi is there, meaning he returned before hetian) + ch436 could takes place immediately after the other christmas specials, but could potentially also be another winter in the future)
*ch443: adults

ch446-451: adults, all boys reunited (you can see that time has passed since ch445, because all mo’s injuries are healed; this is potentially even further in the future, because the boys seems to have settled into their usual dynamic)

ch452-461(latest): adults, seems to take place not too long after christmas as mo is still warming up to hetian again. potentially new main timeline.

this doesn’t include all specials or extras, but in general the those seem to be set in their adult years, and same goes for artwork. it’s indicated by the content, height, fashion or whatnot, e.g ch396.5 is a timeskip bc mo has his cartilage piercing which he hadn’t gotten in the main story yet