>>96430247
If you get down to it, this "spring break" constitutes an rite of passage into adulthood.
Something something elven society is highly ritualistic — a necessity born of need to get the various elders, each with their own set routines, to not get in each other's way.
Also, I don't know a cake that can keep for 80 years. Elven pastry must be something extraordinary.

>>96430258
Sounds about right. At some point we ourselves went with age of "adulthood" from 15 to 18, then some went from 18 to 21.
If life expectancy, and especially the duration of the physical prime, grows further, we should expect to see the age of adulthood pushed further.
Seems like a normal practice, to be honest. Whether that's a good or a bad thing is another matter.

>>96430276
>have them start at late teens like everyone else
This. Unless player explicitly wants to play a wizened old by human standards elf, in which case they should work something out with the DM to make it work.
Playing a young (<100yo) elf makes it easier to relate to others, especially the party members. Not everyone can pull off a detached immortal, far from it.
This makes starting age feel almost like an afterthought, with no regard for the life experience even the most sheltered of elves would accumulate, unless they were brain dead the whole time.