Passengers arriving at Sydney’s Overseas Passenger Terminal on cruise ships will find themselves disembarking in two shifts, if a plan to host two ships a day takes off.

The latest bid to increase the capacity of Australia’s most popular port will see vessels arriving in the early hours and leaving at lunchtime, with another taking its place and setting sail in the evening.

The first test of the rapid turnaround is expected in the New Year, when two mega ships from different companies are considering trialling the port’s ability to disembark and re-embark some 5,000 passengers in just a day.

At present, ships arrive at dawn, and generally leave around 5pm.

While the Port Authority would not name the vessels considering the trial until a final decision has been taken, Sydney Harbour Master Philip Holliday said they were home ported and sailing on short cruises.

Mr Holliday said the port had been trying to convince cruise lines to try double berthing for some time, as the industry wrestles with increasing demand and finite capacity.

Neither of the vessels involved in the potential trial could get under the bridge to use White Bay, and itinerary changes now made double berthing a real possibility.

“We’ve been talking with cruise lines to come up with ways to increase capacity using the existing infrastructure”.

The challenge, he said, was in getting passengers, luggage and waste off, cleaning and making up cabins, restocking kitchens and refuelling engines and loading passengers and luggage back on – all in a very few hours.

But he pointed out when Ovation of the Seas arrives in Sydney, the Overseas Passenger Terminal would be taking care of almost 5,000 passengers every time she docked.