Warning!
I bricked my compute stick by doing an online update to Win 10 from 8.1 when the stick told me it was all ready. Now all I can get into is the BIOS, and that doesn't help any. I shall return it, and stay with 8.1 for the foreseeable.
It turns out that many ICS users have had the same problem -- have a look at the Intel website, - community support - Compute stick. There may be a bit of a storm brewing there, and no clear answers as yet.
Were I you, I'd avoid doing any OS upgrade on the ICS until things clear a bit. If you must upgrade, be sure to install the latest BIOS, as the upgrade will fail (Intel says) with older BIOSes. Yes, I did.