anchor.diff:                         []    -> does_not_exist_because_upi_is_empty;
                          [_|_] -> lists:last(NewUPI_list)
                      end,
  -    Repairing_list2 = [X || X <- OldRepairing_list, lists:member(X, Up)],
  +    Repairing_list2 = [X || X <- OldRepairing_list,
  +                            lists:member(X, Up),
  +                            not lists:member(X, OldWitness_list)],
       Simulator_p = proplists:get_value(use_partition_simulator, RunEnv2, false),
       SimRepair_p = proplists:get_value(simulate_repair, RunEnv2, true),
       {NewUPI_list3, Repairing_list3, RunEnv3} =
  
positive.code:             react_to_env_C300(P_newprop, P_latest, S);
  
          %% A40b (see flowchart)
          P_latest#projection_v1.author_server == MyName
          andalso
          (P_newprop#projection_v1.upi /= P_latest#projection_v1.upi
  
negative.code:     {noreply, S};
  handle_info(tick_check_environment, S) ->
      {{_Delta, Props, _Epoch}, S1} = do_react_to_env(S),
      S2 = sanitize_repair_state(S1),
      S3 = perhaps_start_repair(S2),
      case proplists:get_value(throttle_seconds, Props) of
  