I already answered this question in your support ticket, but I will quote my reply also here so that it can be visible in our community.
No, the chart does not expose a behavior that controls the way the empty points are displayed. By default if a data point has a value of Null it won't be plotted on the chart.
For example if you have a categorical data and you have a data point in category "1" with a value set to 10, another point in category "2" with value set to Null and third point in category "3" and value set to 20, the chart will drop the null point and won't draw a line between the first and the third points.
In order to achieve your requirement you can set Null value on the data points that you consider as missing. You can take a look at the Empty Values demo that demonstrates such approach.
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