There's another mode of analysis available about the rate of maturation of Elves. Beleriand's history in FA is relatively short, some 500 years, it would seem.
I don't see indication of 200 year maturations being viable in this setting, in a generational legacy of Elven births. For example, Gondolin is constructed in 54, Aredhel leaves Gondolin at year 104, presumably not as a child. (anyone dispute this?) Maeglin is born in 320. Gondolin falls 510. He was 190. Definitely fully mature.
Earendil and Elwing born 503, depart for Valinor 525. This one, in my reading is pretty influential (Elwing was 3 parts Elf, 1 part Man). They didn't get to Valinor until 542 - I didn't realise that journey took them so long
Anyhooz, she was 22 by the time she was on a boat with her beloved.
Dior Born 470, weds Nimloth 497 (27).
I am annoyed that significant elfy births aren't so prominent, and with the notable absence of indications of their maturation, so, we have a lot more half-elfy ideas. I'm not sure this should be taken as a problem. Wombs. Gestations. Etc seem pretty similar as do developmental trajectories.
The elfy materials are somewhat less definitive, but do have some implications about maturation, in a "not greater than" statement. Aredhel, 104 years.