What map are you using?
I think the following extract made it pretty clear:
...a flat earth where trans-pacific flights that cross the international date line are possible at least...
But, since there seems to be some confusion; I was referencing the mono-polar map.
There are multiple proposed maps.
And no flat map has ever been made that accurately represents the size, shape, and layout of the continents. Flat maps that give an approximate representation exist, such as the commonly used Mercator projection, but they only exist as a convenient means of viewing all continents at once, they are not an accurate representation of the earth.
I am not counting navigational charts, which only cover small sections of the earth's surface. Small areas can be represented with reasonable success (read: with some distortion still present) on flat maps, which certainly makes packing a few maps in your flight bag a lot easier for pilots!