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A subscription_bundle that is used by rollover bundles, utilizes all four value parameters:
VALUE_1- maximum number of units inside bundle,VALUE_2- total number of units used (the sum of units used inside the bundle's own periodby the bundle itself and by other bundles (when the bundle is used as a surplus bundle)),VALUE_3- maximum number of units, that can be rolled over (the maximum number of units that can be used as surplus by other bundles)VALUE_4- number of used rollover units (units used outside the bundle's own periodbasically value_3 minus value_4 indicates how many units can be used as surplus. However, note that value_4 is not a simple value, it is used as "a value from which other information can be calculated" (for more information, see below).
Value_4 Explained
The rules for how/when to update value_4 are:
- When the bundle is used as a surplus bundle by another bundle, then value_4 is updated with the amount of units used by that other bundle.
- Note that the process that updates value_4 shall make sure to also update value_2 with the same amount of units.
- When value_2 is updated it needs to be checked if the total units available in the bundle is now less than the number of units that can be used as surplus. If this is the case, then value_4 needs to be updated such that this is no longer the case.
- In more mathematical terms, if (value_1-value_2)<(value_3-value_4), then adjust value_4 such that the '<' becomes '='. This means that value_4 shall be set equal to value_3-(value_1-value_2).
Subscription Bundle Update Manager
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