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Volume ordered is constrained by the account balance (if the EFN is managed by the EFM), whereas Residual Requirement is not. The volume is calculated at the order phase. Volume ordered will be deducted during ordering phase for order debit or during flow phase for use debit. For order debit it will debit the order at min travel time (i.e. the number of timesteps between the EFN and the closest storage/weir node). For example: if there is a EFN and a storage node with 2 days travel time - if an order is placed on the 1/1/2000 it will be debited on the 1/1/2000 in order debit (i.e. when the order is placed in the system). For use debit, the account is debited on the 3/1/2000 (i.e. when the water arrives).
Timesteps Spell is Actively Ordering: The number of timesteps a spell will attempt to place orders. This gets reset after the spells fall phase. This is used in environmental flow manager functions to determine if an action is currently ordering.
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