docs: private void useFallbackBackends() {
      usingFallbackBackends = true;
      logger.log(ChannelLogLevel.INFO, "Using fallback backends");
  
      List<DropEntry> newDropList = new ArrayList<>();
      List<BackendAddressGroup> newBackendAddrList = new ArrayList<>();
      for (EquivalentAddressGroup eag : fallbackBackendList) {
        newDropList.add(null);
        newBackendAddrList.add(new BackendAddressGroup(eag, null));
      }
      useRoundRobinLists(newDropList, newBackendAddrList, null);
    }