It looks like WD removed 2.31.193

I have upgraded it after been promised by their support it will fix some issues I have with the standby mode (it’s spin every 20 minutes instead of standby when not in use for days)

it looks like now the latest version according to their website and the release notes is 2.31.183

Some where having trouble with 2.31.193 on the single bay where USB drives stopped being recognized. Perhaps WD pulled it due to that.