State Transport Minister Gladys Berejiklian has declined to say whether trains on the South Coast line will run faster under the new timetable.
The revamped timetable will be released several weeks in advance of October 20, when it will take effect.
However, there is no indication that train speeds will be increased, as per recommendations last year from Infrastructure NSW (INSW).
As part of its strategy for government spending over the next 20 years, INSW said a quicker train trip from Wollongong to Sydney was a priority.
INSW chief executive Paul Broad said at the time that a one-hour trip should be one of the "core operational objectives" for NSW trains.
"These trains can go a lot faster," Mr Broad said.
"We're challenging State Rail to really look at their scheduling and their mindset's been that we have to slow them all down and that's the only way we can run them safe."
Ms Berejiklian did not respond to questions about whether the new timetable would rely on some trains going faster.
She did, however, say some passengers could expect reduced travel times.
"Customers who travel longer distances from outer suburban areas will notice fewer stops and reduced journey times in many instances," Ms Berejiklian said.
She added that one of the aims of the new timetable was to deliver more express services across the rail network.
Ms Berejiklian said there would be more than 1000 changes to the old timetable as well as "several thousand more operational changes".
She attempted to allay community concerns about the contents of a leaked draft timetable, which she said was a draft.
"I would urge everyone to wait until the government releases the final timetable before they make judgment."