Last week a bunch of people were complaining about it not hitting the UK store last week for some unknown reason. I have yet to see a response from WBI, so I have no idea. My buddy in the UK said he made an American account and bought it that way. That's one way to do it if you want. Not sure why it hasn't hit the UK store. So it didn't pop up with the update last night?
If you search "kombat" it definitely shows, so if you don't see it then it's not available there yet and no, I have no idea when it will.