8.1 not showing

Just bought a new Alienware 18 that came today. Can't update to 8.1 as it doesn't show.

I did the expected things first. I went to Windows Update and installed the updates, then re-ran to ensure there weren't any more. I checked the update specifically related to KB articles at Msft saying it needs to be installed to make 8.1 show up in the app store was installed. I even checked that my license install from Alienware was a 'proper' OEM and not some odd Volume license thing gone wrong (which is one reason Msft says it won't show).

So... I pass all the suggestions in the KB articles that mean it SHOULD show up as an update option. But it doesn't. I'd kinda like to update - looking at the forums this should have all the right drivers etc so it should be a safe update (and worst case I only got it today so can easily rebuild or use the disks that came with it).

Anyone got any suggestions or thoughts? I'm at a loss. If only Msft would have an easy option for downloading a redistributable file like in the good old days. they really are making this frustratingly hard...

UPDATE: Sorry, can edit but can't seem to delete. Turns out if you do the same thing over and over again you CAN get a different result... After playing with stuff and rebooting more times, with one additional change (updated Alienware command centre) it now shows in the app store. surprised by that, but seems as though it's ready to roll...