Continental rip, which is what occurs during pole shifts rather than continental drift, occurs down the length of the Atlantic Ocean. Prior to the rip, there is tension and consequent dragging down of the coast line on either side. The East Coast of the US south of the New England area will suffer during the pole shift, due not only to the heavy population of the area but also to this general stretching that the plates under the Atlantic during the crustal tension ahead of the shift, with the crust resisting a ripping apart so that the land on the edges of the Atlantic Ocean are pulled down. This is most intense the closer one gets to the equator, so that the southern states along the Eastern Seaboard of the US will go under water to a surprising degree, bouncing back when the rip occurs.
The closer one gets to the Arctic, the less tension there is, due to the position of these point relative to the bulk of the land masses on these plates, which center south. This will bring the islands in the British Isles underwater, and along the southeastern US too for an astonishing drop in level beyond what the inhabitant think possible. The New England states will find themselves bouncing up during the shift, due to the quick ripping of the already separating St. Lawrence Seaway prior to the shift, where the southern states will find themselves pulled under the water prior to the shift. The entire peninsula from central Pennsylvania north, will experience a bounce, but being on the edge of this drama, Pennsylvania will have its toes in water but its head above water.
Where tidal waves elsewhere will in general have the potential of rolling a hundred miles inland to a height of 200 feet or more within that buffer zone, for the East Coast south of the New England area, this must be calculated to be up to 500 miles inland where flat land or tidal bore has facilitated water flow. The land will drop in sea level, during the shift, 150 feet. The water will rise steadily, not in a tidal wave, so that it will take many by surprise. This tension, and dragging down, will not be relieved until the shift itself, so where land might eventually be above water, prior to the sift it will be under water. Thus, the majority of the populace not well into the Appalachian mountains will drown.