Panning in DateAxis with a range outside the data range

I have this x axis:

private fun createxAxis(builder: SciChartBuilder, firstDay: Date?): DateAxis {
    val weekAgo = Calendar.getInstance().let {
        it.time = Date()
        it.add(Calendar.DATE, -6)
        it.time
    }
    val today = Calendar.getInstance().let {
        it.time = Date()
        it.add(Calendar.DATE, 1)
        it.time
    }
    val historicalFirst = if (firstDay != null) {
        Calendar.getInstance().let {
            it.time = firstDay
            it.add(Calendar.DAY_OF_MONTH, -1)
            it.time
        }
    } else {
        weekAgo
    }

    return builder.newDateAxis().apply {
        withDrawLabels(true)
        withDrawMajorBands(false)
        withDrawMajorTicks(false)
        withDrawMinorTicks(false)
        withTextFormatting("E")
        withTickLabelStyle(
            FontStyle(
                ResourcesCompat.getFont(context, R.font.proxima_nova_400),
                context.resources.getDimension(R.dimen._9sdp),
                resources.getColor(R.color.white, null),
                true
            )
        )
        withAutoFitMarginalLabels(false)
        withDrawMajorGridLines(true)
        withDrawMinorGridLines(false)
        isEnabled = true
        withVisibleRange(weekAgo, today)
        withVisibleRangeLimit(historicalFirst, today)
    }.build()
}

and this pan modifier:

    private class CustomXAxisDragModifier(
    val gestureCallback: WeakReference
) : XAxisDragModifier() {

    override fun performPan(xDelta: Float, yDelta: Float, isSecondHalf: Boolean, axis: IAxis) {
        super.performPan(xDelta, yDelta, isSecondHalf, axis)
        when (axis) {
            is DateAxis -> {
                gestureCallback.get()
                    ?.onVisibleRangeUpdated(axis.visibleRange.min, axis.visibleRange.max)
            }
        }
    }
}

val panModifier = CustomXAxisDragModifier(WeakReference(callback)).apply {
    dragMode = AxisDragModifierBase.AxisDragMode.Pan
    minTouchArea = 1000.0f
    clipModeX = ClipMode.ClipAtExtents
    clipModeTargetX = ClipModeTarget.VisibleRangeLimit
}
surface.chartModifiers.add(panModifier)

When I load this chart with data, it looks correct (see first screenshot). But the moment I try to drag it, the chart clips to the most recent data point (see second screenshot) instead of what I’m setting as the visible range limit. The most recent data point is a few days before today. How can I get the panning to clip at the visible range limit?