Since the light we receive from distant galaxies may be between 7 and 14 billion light years away, the redshift we see indicates that the universe was expanding at that time (7 to 14 billion years ago). If the universe started collapsing today, we wouldn't know it for perhaps 7 billion years. Why are we so sure the universe is still expanding (based on that old information), especially since closer galaxies like the Andromeda Galaxy exhibit a blueshift and are assumed to be moving toward us?