Obviously, that's not a joke.
The changed specification is also present prominently on the KS product site, and our German distributor DataTec already has an updated full data sheet with the reduced max. voltages.
Keysight does not have that updated, full datasheet, yet. There's the addendum only. Very strange.
Did some safety standards (norms) change recently, or did they really find a weakness for the input circuitry?
Anyhow, it's not ok, that owners were not informed directly.
Frank