Fixed points · The immovable · Element
The preparation
When work has to start to meet it.
The part
What it is
Backwards from the date by the actual preparation time, which is what should be in the plan rather than the deadline itself.
A fixed date in a plan with no start date attached is a fixed date that is met at the last moment.
The smallest level
The attributes it carries
Each attribute is one of the framework’s shared types. What a date is, and how it is written, is defined once for the whole model — the note here says what it means in this particular place.