how soon is "immediately"

[ehem]

If denied for extension of stay as a visitor and asked to leave immediately,
how much long you can still stay considering arranging for your flight?

 

[job_seeker]

Usually 30 days.

If denied for extension of stay as a visitor and asked to leave immediately,
how much long you can still stay considering arranging for your flight?

 

[Baloo]

If denied for extension of stay as a visitor and asked to leave immediately,
how much long you can still stay considering arranging for your flight?

Using the words "arranging for your flight" means zero, a flight can be booked in minutes online.
Booking in the afternoon and leaving that night is possible.
FWIW Immigration have no interest in the added cost of booking flights traveling at short notice.