500 Above,
Kalimera, one of many benefits with the design of the hybrid is to negate the need for ballast when off-loading. It is not totally reliant on the gas for lift. The disadvantage of this is an increased fuel burn in proportion to the load like any conventional aircraft.
I do not know about the operational aspects regarding temperatures and pressure altitudes. However again, this may be overcome with aerodynamic and vectored thrust lift.
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