Type Alias RuleFindingBand

The care period one answer is about.

key is the program stay's id and never its name: two separate Residential stays are two bands, and swapping the label for a level of care later is then one expression rather than a regrouping.

type RuleFindingBand = {
    endedOn: string | null;
    key: string;
    label: string;
    startedOn: string | null;
}