Next-due date (when the current dose lapses). Not the vial expiry — see DateTime? VaccinationRecordDto.VaccineExpirationDate.

Physical vaccine vial/lot expiration date (distinct from the next-due DateTime? VaccinationRecordDto.ExpirationDate).

True when the underlying inventory lot is a temporary placeholder awaiting resolution. Certificate generation is blocked while this is true.

True when the dose was retracted (billing line voided, or a mis-entry corrected). The record stays on the chart for audit but is not a valid dose: it drives no reminders, does not count toward vaccination status or schedule stage, and cannot be certified. Render it struck through.