@el-berto,
Please refer this article for more information on array shift method in JavaScript.
If you are still facing any issue with CanvasJS, kindly share JSFiddle with your use-case so that we can look into the source code, understand the scenario better and help you out.
From what we have observed, sometimes things get delayed mostly when we are not able to reproduce the issue or not able to understand the exact requirements or the solution that we provide may not work properly due to the variation in chart-options being used by you and us.
Having a JSFiddle helps us in figuring out the issue and many a time we can just edit your code on JSFiddle to fix the issue right away.
—
Vishwas R
Team CanvasJS