protected Instant expireMixedBaseOnRule(
      DataExpirationConfig expirationConfig, Types.NestedField field) {
    Instant changeInstant =
        Optional.ofNullable(changeMaintainer).isPresent()
            ? changeMaintainer.expireBaseOnRule(expirationConfig, field)
            : Instant.MIN;
    Instant baseInstant = baseMaintainer.expireBaseOnRule(expirationConfig, field);
    if (changeInstant.compareTo(baseInstant) >= 0) {
      return changeInstant;
    } else {
      return baseInstant;
    }
  }
Table maintainer for mixed-iceberg and mixed-hive tables.
amoro-ams/src/main/java/org/apache/amoro/server/optimizing/maintainer/MixedTableMaintainer.java