The calendar · Seasonal moments · Element
The lead time
How far ahead work has to start.
The part
What it is
Counted backwards from the moment through production, review and approval. Most seasonal work starts at the point where only a rushed version is possible.
The start date belongs in the calendar as a scheduled item, not as an intention held by whoever remembers.
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.