Sillage is independent of the phase of notes pyramid - it depends on the fragrance composition. Sillage is mainly dependent on the notes and their concentration - an EDT concentration fragrance with main notes of citrus wont project as much as an EDT concentration fragrance with notes like amber and incense because amber and incense are denser than notes like lime, orange, etc. It could also be that a fragrance might use comparatively more tenacious notes like lavender or rosemary in top notes - in this case, the top notes will be perceptible longer than in a fragrance where the top notes contain ephemeral notes like grapefruit, lemon, etc. Whatever the case, top notes evaporate faster than heart/base notes which form the heart (no pun intended) of a fragrance's sillage.