You got updates for Telerik MVC Extensions via Telerik Control Panel because we still deliver maintenance releases for them, as stated in the FAQ I pointed out (and we shipped maintenance release for them last week).
You will get the updates for Kendo UI Complete for ASP.NET MVC once we release a new version of this product, which is due in the middle of next month.
Hope this makes sense and the guidelines from the public FAQ will help you choose which product to use in your case.
the Telerik team
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