Diamonds not generating in deepslate

Diamonds don't seem to be generating in deepslate. I've cleared multiple chunks but have only found normal diamond ore, not the deepslate variant. Chunks that try to generate the diamond ore blob in the deepslate end up not generating diamond ore at all. From what I've read in the changelogs, none of the ore generations have been modified in this update so there should be one diamond ore blob per chunk.