Couldn't find a specific location to report bug feedbacks (unless we missed it!) so thought it would be best to post here.
We have been configuring a Ready NAS Pro 6 to deploy and decided to simulate a disaster (fail to plan - plan to fail and all that)
Anyway, we have 4 drives in there, which we have configured as two sets of RAID 1 (giving volume C and D). Volume C was fully sync'd and Volume D was sync'ing. We decided to pull a drive from Volume C. NAS duly detected failure. Inserted another disk of same size and it reported it would sync the Volume C after it had completed the current task (sync'ing Volume D).
Volume D completed, however Volume C never began its sync process. We had to remove and re-seat the drive for it actually perform the task it had promised to do earlier!