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Please note that for simplicity you cannot link an external price component to another that already has a parent price component. (for example, given three external price components A,B and C, if B→C then A → B → C is not permitted)
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When defining the amounts int the price breakdowns, the child external price component will appear right below it's parent component. If you select a child price component, it will automatically select its parent.
In the amount table, you can differenciate children components from parent components with the shift before their name.
Validity dates for rates tables price breakdowns
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