ok, thanks. Then I may eventually spend some time experimenting. If it works, I will report back. For now, other pressing issues have come up so I have to take chances (and move some of the more frequent changing application specific (log)files to one of the existing tmpfs portions and hope to reduce the risk of fs corruption beyond fsck automatic repairs)
I must admit I am surprised this feature was not requested by most users of armbian - when choosing the sbc+armbian combination I had expected this was a typical scenario and would be covered; error on my side, live and learn, I guess