gistfile1.txt

Given:
                       J
                      / \
        B--------I---E---K      master
       /        /
      /       B1      <--- last import replayed B
     /       /
    A---C---D---F---G---H       upstream/master
    
Note 'I' is the previous import merge commit.

Attempting to linearise tries to create an initial import branch looking like import/next:


                       J
                      / \
        B--------I---E---K      master
       /        /
      /       B1
     /       /
    A---C---D---F---G---H       upstream/master
             \
              B1---E---J        import/next