OTL Timecard entry - restrict the selectable charge codes to COA child nodes

Summary:

OTL Time Card allows staff to override their costing string if the overtime is to be charged to a different source than their salary.

These fields are called Chart, Fund, Organisation, Account, and Activity and align to our chart of accounts segments. The OTL fields reference the COA value sets for the corresponding segment.

However, staff are able to select PARENT codes with ('Allow Posting' = NO) within the value set.

Is there a method to have OTL to reference the value set dynamically so staff are unable to view/select PARENT codes (with Allow Posting = NO)? 

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