Yep that did it, on build 920 and reset all settings then set balancing as you said. Overnight it reached about 99% balanced (not exactly perfect) but close enough!
Thank you!!
Christopher,
Appreciate the help, once I mounted the drives and set them to online all of my data was visible. I have now reconstructed all of my data from my 5 drives without issue.. ie nothing was lost. Been using Drive pool since day one and its never caused me to lose data!!