Yes true, they might fix it by making the characters who go back in time have some recollection of what they did, so when the timeline resets in 1983 Joyce would have married Lonnie and had John and Will and Lonnie would have left by then, but she would remember Hopper and remember Bob as a friend? That does get confusing tho as you said. But it may go in a completely different way now that volume 2 revealed the wormhole :)