To qualify for year ended 30 June, 2020 you must have the equipment (including cars) installed ready for use and paid for (or invoiced, if you use accruals) by 30 June, 2020.
The measure has now been extended to 31 December, 2020 for half of next financial year. WARNING: the extended measure is not law as yet. Federal Parliament will not sit again until 4 August, 2020.