Adjusting the Shape of the Frame Borders
Once the frame borders are split, you can use the [Object] tool to adjust the shape and size of the border lines in the same way as with the balloons.
Bleed Settings
Clicking one of the triangular handles allows you to extend the border line to the edge of the canvas, the crop marks and/or the adjacent frame border(s) and make the frame a bleed frame.
Extend the first frame border upward and to the right and extend the fourth frame border downward.