Sometimes an end city generates a bit burried. When the ground level is so high that even the enterance shulkers would be burried, the end stones in their locations will not get removed, the shulkers will get suffocation damage and then teleport. I have seen and end city where this happened with both shulkers but sadly I was unable to find it again. An end city where this happened with one of the shulkers is at -6050 1025 in end with world with seed 3519906154027311463. I was actually unable to test this on 1.16.2, but surely affects 1.16.1.