CREATE STATISTICS MT_ReservationDepartureUtc (ndistinct) on "AccountCode", "DepartureUtc" from "Reservation"."Reservation";
CREATE STATISTICS MT_ReservationArrivalUtc (ndistinct) on "AccountCode", "ArrivalUtc" from "Reservation"."Reservation"; CREATE STATISTICS MT_ReservationNoShowFeeId (ndistinct) on "AccountCode", "NoShowFeeId" from "Reservation"."Reservation"; CREATE STATISTICS MT_ReservationTimeSliceDefinitionId (ndistinct) on "AccountCode", "TimeSliceDefinitionId" from "Reservation"."Reservation";
but that didn't help either
Did you try with 'dependencies' for the statistics_kind or only ndistinct? What was default_statistics_target set to at the time you created the extended statistics? I am not sure if that value is used, but I would assume so.