The End Is Sort Of Nigh

So far, human beings have managed to avoid being completely eradicated like so many species in the history of life on Earth but scientists put the Earth at halfway through a 10 billion year life-span after which it will run out of energy, expand and engulf us all but hey, we got another 5 billion years to worry about all that so party on, or so we thought.
Scientists at  the University of Toho in Japan have crunched the numbers and come up with a date when life will become hospitable, and it is a lot less than 5 billion years.
The Sun's death will be a slow process but they have taken into account atmospheric conditions and the reduction in Oxygen, rising temperatures and deteriorating   air quality and pegged the date for when life will be completely unable to survive on Earth as the year 1,000,002,021, give or take a few years.
My calculator shows that we've got around 999,999,995 years left which seems a long time but it's a lot shorter than the original 5 billion years we thought we had although the way things are going, we will be long gone by then anyway.