According to a graph shown by Henrik Kniberg, Redstone should generate below Y = 16. In the latest beta, Redstone can generate at Y = 32 which should not be the case.
On java, redstone is more common the deeper you go. On bedrock, Redstone is most common on Y = 0.
Can confirm, redstone ore can be found well past y=16 and up to y=32. By simply changing the distribution number in the json file, the ore distribution is fixed.
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