Everything from MS seems to point that this version is not final or maybe it is and will be tweaked. But I can honestly say that are still some major drawbacks with this update compared to the previous ones. I for one have a major bug with Office 365 that crashes after an upgrade with any insider builds. I can also see some other users have problems also. It would be nice if Dona could be a little clearer as to if this build is final or not. Not that in my case it matters because I won't install this on a working machine because it's not up to par. But I would like to test a bit more and continue to submit issues.
Download ISO from Build 15058, opt for insider builds and download it, copy the UUP folder and use the program listed in OP.
agree there be like million ppl right now want make the upgrade msft is not so stupid make ppl upgrade in non "rtm" build ....