I just had a Microsoft Level 2 tech support perform a repair install of 8.1 on my 8500 that came with 8 but I upgraded to 8.1 from the Windows Store . She could not  the important windows 8.1  update  1 " KB 2919355" to download and install and did the repair install option which did the trick . She also left me an ISO file that she said I could use to do the same in the future if needed  or reload it with the ISO if hard drive crashed instead of using my recovery disc and having to go through the 8.1 upgrade process again. It seems like she used my product key that came with 8 which I did not think could be done . I was wondering if I could use that ISO to upgrade other 8 machines and entering their product code to activate like she did mine . If so that would seem like a lot faster than having to download and install on each Windows 8 machine I support

She also told me that Windows 8 will be supported through the end of the lifecycle in 2023 with updates , security patches etc. This seems to contradict Microsoft policy of having to update to 8,1 within two years of being made available to continue to receive support . I asked her about this several times and she was quite adamant that windows 8 would continue to receive support whether I updated to 8.1 or not  

Any comments would be appreciated