To go deeper into my response...... your original bond beam height was set to your coping material and skimmer set to the middle of the tile height. Now that has changed. The new tile is probably set to the middle of the skimmer. Your coping is thinner or thick than the original material and I assume was laid level. The bond beam or top of the pool gunite shell is never perfectly level across the whole pool and when the coping is laid down the mortar bed will be thicker and thinner to make the coping level. Some variables changed from the original build to the remodel and the difference is more visible or was not noticed before. This is assuming the tile and coping are level. Hope that helps.