Bug :: Task.duration failing on read. (4.0.2)

In OmniPlan 4.0.2 (v205.7.0) reading Task.duration fails.

Writing works well – we can set a task’s duration, and the results are visible in the GUI, but as a getter, evaluation of .duration invariably returns only null values, even for tasks that do have duration values.

(regardless of whether these durations have been set through the GUI or the API)

Example:

We can create the following data by script or GUI, but the .duration value for each task is invariably reported to be null

const test = () => {
    const
        rootTask = document.project.actual.rootTask;

    [1, 2, 3, 4, 5].forEach(
        h => {
            const newTask = rootTask.addSubtask();

            newTask.title = h.toString() + ' hours';

            // WRITE/SET SUCCEEDS
            newTask.duration = Duration.workHours(
                2 * h
            );
        }
    );

    // READ/GET FAILS
    return rootTask.subtasks.map(
        task => null === task.duration
    );
    //-> [true, true, true, true ...]  :-(
}