The Erin Hunter team sell one or two warriors book in series every year, and also a super edition. But how long does it actually take?
Over the years, the time it has taken has gotten shorter, but not too short! If we look at when the Light In The Mist was released and when River will come out, we can get some idea of how long it takes for a warriors book to be made and released.
A light in the mist was released Nov 9, 2021 and River will be released on April 5th. So around six months if we look at it that way.
I asked the Warriors Website, and here’s what they said:
They actually never responded. So I assume it takes around a few months or so.
WarriorCatsFanBlog 
Probably six months or longer since they don’t announce the book is coming out the second they write it.
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