Does setting `async_execution=True` on a task require using kickoff_async() for the crew?

Crews
1

Hi community,:waving_hand:

I am new in CrewAI. I have a question about the interplay between task-level async_execution=True and the crew kickoff method in CrewAI.

In my workflow, I define a Crew with multiple Task objects. Some tasks are marked with async_execution=True, meaning they can execute asynchronously relative to other tasks. My question is:

If one or more tasks are marked async_execution=True, does that require me to use crew.kickoff_async() (instead of crew.kickoff()) to correctly execute the Crew asynchronously (or in parallel)?
Or can I still call crew.kickoff(), and the tasks with async_execution=True will automatically run asynchronously within that call?

The code is like this:

...

task_one = Task(
    description="List of 5 interesting ideas to explore for an article about AI.",
    expected_output="Bullet point list of 5 ideas for an article.",
    agent=researcher,
    async_execution=True # Will be executed asynchronously
)

task_two = Task(
    description="Research the history of AI and give me the 5 most important events.",
    expected_output="Bullet point list of 5 important events.",
    agent=researcher,
    async_execution=True # Will be executed asynchronously
)

# I expect Agent1 is assigned to task1 and agent2 to task2 asynchronously.
my_crew = Crew(
            agents=[self.agent_one(), self.agent_two()],
            tasks=[self.task_one(), self.task_two()],
            process=Process.sequential,
            verbose=True
        )

# should I use ?
my_crew.kickoff()
# or ?
my_crew.kickoff_async()

I want to understand whether the async flag at the task level is sufficient for parallelism, or whether kickoff_async (or another async-specific kickoff method) is required for non-blocking / concurrent execution of the full crew.

Thank you for any clarification or examples of how this works in practice.

Best regards.