I'm know that most 230V gas filled incandescent lamp have the best lifespan at base-up use.
Is this true also for vacuum incandescent lamp (Like the antique replicas) or they have the same lifespan on both base-up and base-down use?

The base up means greater tgermal stress to the base. So if there is no other lifetime impact, the more frequent failures of the hotter running base may cause the base up position to loose some points in lifetime statistics. But with an adequately designed and manudactured quality product this difference should be very minimal, as dominant would be the plain tungsten evaporation.

Anyway I don't know about life (don't see what mechanism should be responsible for base up being longer life, I would expect the socket issue would make it exactly the opposite, but I definitely don't say there isn't any, I just have no idea what they are), but with gas filled the base up definitely improves the lumen output maintenance, as the evaporated metal condenses in the area where the light can not pass anyway, so the areas where the light can pass stay unafected.

James know about this.

For gasfilled incandescent lamps, the lifetime is always best and as standard reported for base up use.  This is because the gasfilling, which is heated by the filament, loses most of its heat energy to the glass bulb in the base up position.  The neck area of incandescent lamps is scientifically designed to maximise heat transfer from the gas to the glass, which results in slightly lower gas temperature, hence lower filament temperature, and achieving the rated life.  If used horizontally or base down the different gas convection patters result in a hotter filament and marginally increased light output, but shorter life.

Additionally there is an improvement in lumen maintenance when used base up, because evaporated tungsten is deposisted mainly on the inner stem and neck area, which blocks less light than if the bulb crown or side is darkened when burned base down or horizontally.

For a vacuum lamp there are of course almost no heat losses by conduction and convection (except via trace hydrogen impurities remaining in the bulb), and the bulb blackening is uniformly over most of the glass irrespective of burning position.  So you might think that burning position has no impact on life.  However depending on the shape of the filament support wires, these will short-circuit more or fewer filament turns depending on the burning position and where the filament lies.  Once again the reference position is always base up, and most support wire designs are formed such that the filament then contacts a part of the support loop having only one wire.  If used base down, sometimes the support pigtail has two wires side by side, and this may short circuit extra turns leading to an over-run filament, and shorter life.

Thanks James. There are lots of Chinese antique replicas here in Israel, and I don't knew if they have the best life at base up like the regular gasfilled incandescent lamps or that they aren't affected by the burning position.