Yes you are correct. If you update to the latest version, you will no longer be able to use Grid and Upload for free under the GPLv3 license, and you will have to rework the Grid and Upload controls with another framework (unfortunately).
As far as I know, you are also not allowed to use Kendo UI core (Apache License, version 2.0) simultaneously with an older version of Kendo UI Web to take advantage of the missing controls/widgets, as that would imply a dual license.
The following snippet is from an email I received from Telerik:
What does this mean for the license holders of Kendo UI Web GPLv3?
Previous Kendo UI products — Web GPLv3, Web, DataViz, Mobile and Complete—have been streamlined into two licenses: open source Kendo UI Core and the commercial Kendo UI Professional.
To continue developing with Kendo UI you can:
- Download Kendo UI Core and get access to new widgets previously not available open source
- Upgrade to Kendo UI Professional and get access to all HTML5 widgets, plus dedicated technical support by the same developers who build the product
Or you can stay with the GPL v3 license, but know that there won’t be new product updates.
This outlines your options pretty clearly:
- payup (Kendo UI Pro)
- workaround (Kendo UI Core + replacement framework)
- stay as it is but no longer receive new versions (Kendo UI Web)
As far as replacement frameworks go, I can only speak for the grid control as I don't use the upload control, but I would suggest taking a look at jQWidgets. Their grid is pretty well developed and has similar functionality to kendo grid. You can use it for free if you are using their controls for a non-profit project, otherwise it is NOT free.