As I said, this is expected behaviour with Hijack installed.

If no Hijack, then the drives may still spindown, or not, depending on the behaviour of bugs in the v3alphas.

Hijack v371 will be released shortly -- it halves the spindown timeout that Hijack imposes when a v3alpha release is detected. This will result in faster spindowns than at present, to help compensate more for the v3alpha behaviour.

Cheers