HSC students are being advised to check the new rail timetable that began on Sunday.
The changed timetable has caused some controversy in the northern suburbs of Wollongong due to the replacing of direct trains with local services.
In Sydney, the train timetable will be rolled out alongside new timetables for public buses and ferries.
A Transport for NSW spokesman advised people to plan their trips in advance to ensure they were not late.
‘‘We want to remind HSC students to check the new timetables so they get to their exams on time,’’ he said.
There are several options for planning your travel – via 131500.com.au, the Transport Info Line on 131500 or downloading the New Times app.
‘‘The new timetables bring improvements for the vast majority of public transport customers, whether that’s in a reduction in journey time, regular and consistent service times or improved connections between different types of public transport,’’ the spokesman said.