The session you skip is the one you needed

Nobody cancels when they feel terrible. They cancel in the week they finally feel fine.

I understand it completely — the pain went quiet, the week got full, and the appointment looked optional. But the quiet week is the one where the work actually holds, because we are no longer chasing a flare-up. We are building the thing that prevents the next one.

This is the entire argument for a package rather than a single session. Not because three is better than one in some abstract way, but because the third session lands in the week you would otherwise have skipped.