Hello Danny,
In order to update the underlying array you will need to have the transport configuration for the dataSource. If you want to use custom function, maybe this example can help you achieve that:
http://docs.telerik.com/kendo-ui/web/grid/how-to/grid-localstorage-crud
It shows how to update the internal arrays correctly, after you have updated the remote service as well.
Regards,
Kiril Nikolov
Telerik
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