AUM usage for 'past agreement date RUPs'

A need to have plan dates extending past agreement dates for some renewals means that the AUM Usage information will have a gap (from date of agreement end to plan end date). This issue is to track the work on the solution to extend usage data past what FTA sends to MyRangeBC.

No file, test, or entry point is named. Start by locating the AUM Usage and FTA data flow in the range-ios project, then clarify how renewals with plan dates past agreement dates should be represented. Done means usage data covers the period through the plan end date without a gap.

Written by the indexing model from the issue text.