Socrates is right, Hanover would definitely be restored in an 1870 peace. Even if Hanover united the two halves of the Prussian Kingdom, It was still quite possible, given the short span it was from Annexation in 1866 to their hypothetical defeat in 1870-1871. Even if it was not a total defeat, the best France (and Austria should they intervene) is the restoration of at least the pre-Austro-Prussian War borders is the most feasible.