The black is the current line. The line could either tunnel along the green line (dashes = tunnel) or flyover the orange line (dashes = elevated). Neither of these are particularly inconceivable. All the land is either unowned grassland or council owned grassland, it wouldn't add more than 2 minutes to a trip (plus one extra stop). Of course I'd suggest they simply put in two level crossings as the line only gets 6 trains an hour in peak, but the government clearly won't do this, as indicated by already pointlessly wasting money on this crossing which doesn't need to be removed at all.
What do you think? Conceivable?