public int requeuePendingTasks(String taskType) {

        int count = 0;
        List<Task> tasks = getPendingTasksForTaskType(taskType);

        for (Task pending : tasks) {

            if (systemTaskRegistry.isSystemTask(pending.getTaskType())) {
                continue;
            }
            if (pending.getStatus().isTerminal()) {
                continue;
            }

            LOGGER.debug(
                    "Requeuing Task: {} of taskType: {} in Workflow: {}",
                    pending.getTaskId(),
                    pending.getTaskType(),
                    pending.getWorkflowInstanceId());
            boolean pushed = requeue(pending);
            if (pushed) {
                count++;
            }
        }
        return count;
    }
This method removes the task from the un-acked Queue

@param taskId: the taskId that needs to be updated and removed from the unacked queue
@return True in case of successful removal of the taskId from the un-acked queue
core/src/main/java/com/netflix/conductor/service/ExecutionService.java