D02 — Winter booking ledger cover

The structured register has 48 authorised commitments: 24 island circuits, eight stores runs, four laboratory transects, six pump services and six maintenance periods. Every row has a permanent ID. Its customer, islands, duration, vessel and week are current constraints; they are not categories the coordinator can silently redefine.

Kestrel performs two one-day circuits weekly. Morrow carries 1.5-day stores runs in weeks 1, 2, 4, 5, 7, 8, 10 and 11 and two-day laboratory work in weeks 2, 5, 8 and 11. Tern has six 1.5-day repair jobs in alternate odd weeks. Six one-day maintenance jobs complete the set. Each work unit is indivisible in this deliberately simplified model. Existing repair work includes one pump service; extra faults and parts are not unlimited inclusive work.

The default roster is a witness that the winter fits. It is not an order to preserve every staff pairing. Cash receipts are recognised only for completed work and at the recorded receipt week or actual completion week, whichever is later. Science pays a week later. The ledger offers no income for interesting conversations, proposed services or new labels.

Ivo's annotation: “Please retain the original ID on every version; December's invoice query took two hours because 'Bracken run' had become three different things.”