I am raising this bug report to formally capture discussions on the 6.10.0-rc1 release thread relating to a possible bug.
In summary, I have found that emhttpd keeps issuing read SMART events consistently to my array disks, which is spinning them up. The effect is that my usually spun down Array is pretty much spun up 24x7.
Here are the relevant discussions in that thread.
There was some suggestion that the CATurboWrite Plugin or my Marvel Controller (which only has 3 disks of 16 connected to it) could be at fault but I have since removed the plugin and have confirmed that this issue appears to also be experienced by another user @Mathervius who doesn't have a Marvel controller.
Diagnostics are attached.
Chosen minor but really feels a bit more than that. Having the array spun up all the time isn't desirable at all.