Property bindings produce wrong values for Animation.to

import QtQuick 2.15
import QtQuick.Window 2.15

Window {
    width: 400
    height: 300
    visible: true
    id: window

    Text { text: `Coordinates: (${pt.x.toFixed(2)}, ${pt.y.toFixed(2)})` }

    Rectangle {
        id: line
        anchors.centerIn: parent
        width: parent.width // WORKAROUND: Replace with `width: window.width`
        height: 2
        color: "blue"
    }

    Rectangle {
        id: pt
        anchors.verticalCenter: line.verticalCenter
        height: line.height*5
        width: height
        color: line.color
        radius: height/2
        SequentialAnimation { // PARTIAL WORKAROUND: Remove the outer SequentialAnimation; make the NumberAnimation loop indefinitely
            running: true
            loops: Animation.Infinite
            NumberAnimation {
                id: anim
                target: pt
                property: "x"
                from: 0
                to: line.width-pt.width // WORKAROUND: Replace with `to: window.width-pt.width`
                duration: 1000
            }
        }
    }

    Component.onCompleted: {
        console.log("window.width =", window.width)
        console.log("line.width =", line.width)
        console.log("pt.width =", pt.width)
        console.log("anim.to =", anim.to) // This always prints the correct value
    }
}

NumberAnimation {
    id: anim
    running: true
    loops: Animation.Infinite
    target: pt
    property: "x"
    from: 0
    to: line.width-pt.width
    duration: 1000
}