> ## Documentation Index
> Fetch the complete documentation index at: https://terminal49-mintlify-63ede234.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Alert on LFD Changes and Container Availability

> Use Terminal49 webhooks to monitor Last Free Day changes and container availability so you can dispatch pickups before demurrage charges begin.

Last Free Day (LFD) is the deadline to pick up a container before demurrage charges start. Terminals and shipping lines can change the LFD at any time. Terminal49 sends webhook events whenever the LFD changes or a container becomes available for pickup so you can act before costs accrue.

## Events to subscribe to

| Event                                   | When it fires                                                                                                                 |
| --------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------- |
| `container.pickup_lfd.changed`          | The coalesced `pickup_lfd` field changed. See [How `pickup_lfd` is chosen](#how-pickup_lfd-is-chosen) for the source priority |
| `container.pickup_lfd_line.changed`     | The shipping line's Last Free Day changed                                                                                     |
| `container.pickup_lfd_terminal.changed` | The destination terminal's Last Free Day changed                                                                              |
| `container.pickup_lfd_rail.changed`     | The rail terminal's Last Free Day changed for an inland rail move ([Rail Plan](/api-docs/useful-info/entitlements) only)      |
| `container.transport.available`         | The container is available for pickup at the destination                                                                      |
| `container.updated`                     | Container attributes changed (may include holds or availability updates)                                                      |

## How `pickup_lfd` is chosen

The coalesced `pickup_lfd` field follows a fixed source priority. It does not pick the earliest date, and it does not follow the most recently updated source.

1. `import_deadlines.pickup_lfd_line` (shipping line) — used when present.
2. `import_deadlines.pickup_lfd_terminal` (POD terminal) — used when there is no line LFD.
3. `import_deadlines.pickup_lfd_rail` (rail carrier at the inland destination) — used when neither of the above is present. Rail Plan only.

The line LFD wins even when the terminal LFD is sooner. If your demurrage exposure is driven by whichever LFD lands first, do not rely on `pickup_lfd` alone. Subscribe to `container.pickup_lfd_line.changed` and `container.pickup_lfd_terminal.changed` (and `container.pickup_lfd_rail.changed` for rail moves), read the individual `import_deadlines.*` fields from the included container, and compare them yourself to pick the earliest date.

## Handle LFD change events

When a `container.pickup_lfd.changed` event fires, the `included` array contains the full container object with the updated `pickup_lfd` field:

```javascript theme={null}
app.post("/webhooks/terminal49", async (req, res) => {
  const { data, included } = req.body;
  const event = data.attributes.event;

  if (event === "container.pickup_lfd.changed") {
    const container = included.find((obj) => obj.type === "container");
    const shipment = included.find((obj) => obj.type === "shipment");

    const containerNumber = container.attributes.number;
    const newLfd = container.attributes.pickup_lfd;
    const bolNumber = shipment.attributes.bill_of_lading_number;

    const daysUntilLfd = Math.ceil(
      (new Date(newLfd) - new Date()) / (1000 * 60 * 60 * 24)
    );

    if (daysUntilLfd <= 2) {
      try {
        await alertDispatch({
          priority: "urgent",
          message: `Container ${containerNumber} (${bolNumber}) — LFD is ${newLfd}, ${daysUntilLfd} days away`,
        });
      } catch (err) {
        console.error("Failed to dispatch LFD alert", err);
      }
    }
  }

  res.sendStatus(200);
});
```

## Determine pickup readiness

A container is ready for pickup when `available_for_pickup` is `true` **and** there are no active holds. Combine the `container.transport.available` event with hold checking:

```javascript theme={null}
function isReadyForPickup(container) {
  const { available_for_pickup, holds_at_pod_terminal } = container.attributes;
  const hasActiveHolds = holds_at_pod_terminal?.some(
    (h) => h.status === "hold"
  );
  return available_for_pickup === true && !hasActiveHolds;
}
```

For a deeper explanation of holds, fees, and the `available_for_pickup` field, see [Container Holds, Fees, and Release Readiness](/api-docs/in-depth-guides/holds-and-fees).

<Tip>
  Subscribe to both `container.transport.available` and `container.updated` events. The `available` event fires when the terminal first marks the container as released, but subsequent hold changes arrive as `container.updated` events.
</Tip>

## Common patterns

* **Demurrage prevention** — alert when LFD is within 48 hours and the container has not been dispatched
* **Automated dispatch** — trigger a drayage order as soon as the container clears holds
* **LFD comparison** — for demurrage planning, compare `import_deadlines.pickup_lfd_line`, `import_deadlines.pickup_lfd_terminal`, and (for rail) `import_deadlines.pickup_lfd_rail` yourself and act on the earliest date, since the coalesced `pickup_lfd` field follows a fixed priority instead (see [How `pickup_lfd` is chosen](#how-pickup_lfd-is-chosen))
* **Hold monitoring** — watch for `container.updated` events where `holds_at_pod_terminal` changes

## Related

* [Container Holds, Fees, and Release Readiness](/api-docs/in-depth-guides/holds-and-fees) — full guide to hold and fee fields
* [Event catalog](/api-docs/webhooks/event-catalog) — all available events
* [Payload examples](/api-docs/useful-info/webhook-events-examples) — complete JSON payloads