54 am at Sydenham Station seven days a week for its first four weeks of operation.

The line is expected to cut travel times for thousands of people, with patronage expected to grow over time.

Travel between Martin Place and Waterloo should take six minutes, Sydenham to Macquarie University should take 33 minutes, Central to Chatswood should take 15 minutes, and North Sydney's Victoria Cross to Barangaroo is estimated to take three minutes.

Sydney Metro had insisted there were only a 'small number' of outstanding approvals delaying the opening despite concerns from the firefighters' union that it is not yet safe for passengers.

It is unclear if the Fire Brigade Employees Union (FBEU) will support the opening, after state secretary Leighton Drury said he was not convinced safety concerns had been addressed.

An investigation is still being carried out into an outage on the North-Western line on July 13, which left five trains stuck in tunnels for a number of hours.

We acknowledge Aboriginal and Torres Strait Islander peoples as the First Australians and Traditional Custodians of the lands where we live, learn, and work.

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