I converted your ticket to a public feedback portal item so that everybody can vote for its implementation!
While the requested functionality is currently not part of the built-in features of the AsyncUpload, it is important to note that the chunks are sent sequentially in the same way as in the Kendo async. The only difference is that the Kendo concurrent setting enabled you to upload several files at the same time.
As a small token of gratitude for your request, I awarded you with Telerik points.
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