public static void toFudgeMsg(
     final FudgeSerializer serializer, final FlexiDateTime object, final MutableFudgeMsg msg) {
   Temporal best = object.toBest();
   best = (best instanceof ZonedDateTime ? ((ZonedDateTime) best).toOffsetDateTime() : best);
   addToMessage(msg, DATETIME_FIELD_NAME, best);
   ZoneId zone = object.getZone();
   if (zone != null && zone instanceof ZoneOffset == false) {
     addToMessage(msg, ZONE_FIELD_NAME, zone);
   }
 }