From the announcement:
Have you been enjoying the new version of 1p40k?
Well here is a new version of 1pKT! This new version of the game was streamlined to be even faster and more exciting than before, without some of the clumsy mechanics that the old one used to have.
Kill Team is perfect if you have a handful of miniatures on your hand and you want to just have a quick and fun game, or introduce new players to the hobby. Check it out!