Is Nubian ability to build archers faster limited to Ancient Era?

[Narvana]

Nubian ability description:

Civ ability - Ta-Seti
+50% Production toward Ranged units. Ranged units gain +50% combat experience. +1 Production for Mines over strategic resources, and +2 Gold for Mines over bonus and luxury resources.

Yet in the game files, there's also a line specifying the Ancient Era. Does that mean it works only in that specific era?

<Row>
<ModifierId>TRAIT_ANCIENT_RANGED_UNIT_PRODUCTION</ModifierId>
<Name>UnitPromotionClass</Name>
<Value>PROMOTION_CLASS_RANGED</Value>
</Row>
<Row>
<ModifierId>TRAIT_ANCIENT_RANGED_UNIT_PRODUCTION</ModifierId>
<Name>EraType</Name>
<Value>ERA_ANCIENT</Value>
</Row>
<Row>
<ModifierId>TRAIT_ANCIENT_RANGED_UNIT_PRODUCTION</ModifierId>
<Name>Amount</Name>
<Value>50</Value>
</Row>

 

[LeeS]

	<TraitModifiers>
		<Row>
			<TraitType>TRAIT_CIVILIZATION_TA_SETI</TraitType>
			<ModifierId>TRAIT_ANCIENT_RANGED_UNIT_PRODUCTION</ModifierId>
		</Row>
		<Row>
			<TraitType>TRAIT_CIVILIZATION_TA_SETI</TraitType>
			<ModifierId>TRAIT_CLASSICAL_RANGED_UNIT_PRODUCTION</ModifierId>
		</Row>
		<Row>
			<TraitType>TRAIT_CIVILIZATION_TA_SETI</TraitType>
			<ModifierId>TRAIT_MEDIEVAL_RANGED_UNIT_PRODUCTION</ModifierId>
		</Row>
		<Row>
			<TraitType>TRAIT_CIVILIZATION_TA_SETI</TraitType>
			<ModifierId>TRAIT_RENAISSANCE_RANGED_UNIT_PRODUCTION</ModifierId>
		</Row>
		<Row>
			<TraitType>TRAIT_CIVILIZATION_TA_SETI</TraitType>
			<ModifierId>TRAIT_INDUSTRIAL_RANGED_UNIT_PRODUCTION</ModifierId>
		</Row>
		<Row>
			<TraitType>TRAIT_CIVILIZATION_TA_SETI</TraitType>
			<ModifierId>TRAIT_MODERN_RANGED_UNIT_PRODUCTION</ModifierId>
		</Row>
		<Row>
			<TraitType>TRAIT_CIVILIZATION_TA_SETI</TraitType>
			<ModifierId>TRAIT_ATOMIC_RANGED_UNIT_PRODUCTION</ModifierId>
		</Row>
		<Row>
			<TraitType>TRAIT_CIVILIZATION_TA_SETI</TraitType>
			<ModifierId>TRAIT_INFORMATION_RANGED_UNIT_PRODUCTION</ModifierId>
		</Row>
............

 

[Lonecat Nekophrodite]

Name of files that define that Pitati can be built faster in Ancient Era and not in Classical.
And does it has 'constrains' in Modifier (or any associated tables) "Subject to" <Conditions>? if so what is it?