I bought my MyCloud Home 2TB drive in 2018, I think, and ran into this problem once before in 2019, I think. While I understand the necessity to periodically update the firmware of the unit, I find it incredibly irresponsible to initiate a function that will take my unit offline for more than a week with no advance notice, no way to schedule the upgrade so it will have minimal impact on my workflow, and no progress meter to indicate how much longer it will be offline!
I assume nothing can be done but wait. (If anyone has any other suggested course of action, please let me know.) I am shocked that I seem to be the only one that finds this crazy. I have liked the unit and the price was reasonable, but after this, I will have to find something else because this is unacceptable.