At the moment, the exams for VCP-DCV 2019 are based on vSphere 6.7.
For as long as 6.7 remains the current vSphere version, I expect any "2020" label for VCP-DCV would simply be a re-branding exercise.
I guess this would change as any new version of vSphere is released, then there would be new exams to go with the new certification.
The timing of any new vSphere version may influence the timing of any "2020" update to the exams/certification.
I am merely speculating here by the way.
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