Artillery Units & Stockpiled

[76mm]

It's explained on pp 76-77 of the user manual:
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Stockpiled Artillery
Stockpiled is a type of Artillery unit status that represents a battery in position with ample ammo at hand and effective communications in place. Therefore, such stockpiled units are deemed to be more effective. Stockpiling can take place in one of two ways. A scenario designer can place some Artillery units in a stockpiled state at the beginning of a game. It may also be possible for a side to have the ability to stockpile during a game. This latter option depends upon the value of the Side Stockpiling percentage as seen in the Parameter Data. If this value is zero (0), no stockpiling can occur during the game for that side.
An artillery unit that is Stockpiled will be able to fire for longer periods of time,and perhaps with increased effectiveness, without suffering supply problems. In particular,
• A Stockpiled artillery unit fires at an effectiveness modified by the Stockpiled Fire Parameter Data modifier. For example, if this modifier is 100%, then the fire value of Stockpiled units is not modified, but if the modifier is 200%, then the fire value of Stockpiled units is doubled.
• When a Stockpiled artillery unit suffers its first supply test failure, it remains available, but loses its Stockpiled status at that point. Note: while Stockpiled, the supply test applied to a unit uses a supply value that is 75% of normal. For example, if the normal supply value is 80%, then the supply test applied to a Stockpiled unit uses 75% of 80%, equal to 60%, as the supply value for the test.
Provided that a side has a non-zero Stockpile probability in the Parameter Data, then Stockpiling occurs automatically under certain circumstances. In order for an artillery unit to be eligible for Stockpiling, it must not have moved or fired, must not be Disrupted or Broken, and must not have Unavailable status. Being in Travel or Rail Mode does not affect the ability to Stockpile.

The test for Stockpiling only takes place during Day turns using the probability associated with that side. If the probability test succeeds, then the artillery unit is flagged as being Stockpiled. Any Stockpiled artillery unit losses its Stockpiled status if it moves, including by rail.
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