Devon Rex kitten > adult food when?

Hello! I have just read a million and one threads about when to migrate to adult food. I'm hoping someone with rex experience can help me as most people (vets I ask) get a little shocked when I say she's a year old and only 2.6kg (5.7 pounds).

So she turns 1 in 5 days, still has infinite energy, goes through phases of eating all her food and then some of barely touching her food. Her diet is about 1/2 a cup of ziwi peak kibble which I think is all stages as it's all natural air dried pure meat and I give her a tin of Advance kitten wet food morning and night.

So I've read move them to adult food at either 6 months or 18 months so I thought in between (now) would be a nice compromise.. Really I will just be buying adult Advance wet food the kibble will stay the same. But anyone who has done  it before please let me know your thoughts as I have never had any other cats so I don't know if there's any good signs or anything like that especially for rexes! Thank you

I think now would be a fine time to move her to adult wet food. I have several kittens that range from 9 months to just over a year old and I don't feed any of them "kitten" food. Kitten food just tends to be higher in calories, but ziwipeak is good food with a good calorie range so that helps. Ziwipeak makes good wet food too, but it's pretty pricey. 

Interesting question. I didn't know rex cats are supposed to be smaller. Do they just grow more slowly, eventually getting to regular cat size or are they generally smaller as adults. If the former, I guess it's worth feeding kitten formulas for a while longer. If the latter, I think switching to an adult formula shouldn't be any different for them?