Sesonn C1000 generic running 4.4.2 - is there a way to upgrade to 5 or 6 ?

Per the title I bought a Sesonn C1000 of Ebay a year ago that was running 4.4.2, used it for development.

Is there a way to upgrade to 5.x or 6.x somehow ?

Any help much appreciated.
thanks

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