When the East London Line is extended, will it still be called the East
London Line, given then it joins the Overground?

Obviously a precedent has been set with the Northern Line still called the
Northern line in eg Morden. But the fact that they chose an orangey colour
for Overground makes me wonder whether this is not part of a wider idea to
call the whole lot "Overground", in spite of the fact that some of the
current ELL is underground. Should anything be read into the choice of
colour orange for the Overground?