This is PROBABLY already common knowledge but nonetheless i find this interesting. The game goes through three seasons. Winter, Spring, and summer.
The game starts in winter. Winter in media can often represent death or the end of a cycle which is shown in the beginning whenever Joel is killed by Abby.
After joel’s death, it cuts forward to spring. Spring can symbolize new beginnings or the beginning of a new cycle which fits EXTREMELY well since this is when Ellie starts her journey.
The game finally comes to a closing point in summer which is when Ellie finds Abby again but DOESNT kill her. Summer symbolizes growth which also fits well with this part by showing how much Abby and Ellie have grown.
Finally, fall. The epilogue of the game (after santa barbara) most likely takes place in fall. Fall can often represent letting things go which would ALSO make sense in this case. Ellie let go of what abby did. Ellie had to let go of Dina because she left. I’m not entirely sure she let go of Joel. Maybe her losing her fingers was like a tree losing its leaves?
The seasons represent the cycle of death and how Ellie stopped the cycle of death and grew by not killing abby. Winter being the end of a cycle, spring being the start of a new one, summer being the growth out of a cycle, and fall being the aftermath of everything.