Some commuter train services on certain stretches of the North-South and East-West lines may begin later at noon on some Sundays.
The plans come as the replacement of timber sleepers - which support the tracks - are being accelerated for the work to be completed by 2016 instead of 2019.
This may mean suspending train services on a number of Sunday mornings to allow more time for engineering works.
Public transport operator SMRT and the Land Transport Authority (LTA) are working on the implementation details, including bus bridging services. SMRT said commuters will be informed in advanced.
Currently, engineering hours are between 1.30am to 4.30am, during which only about 90 sleepers can be replaced.
To date, only six per cent or 11,000 of the 188,000 timber sleepers of the ageing lines have been replaced.
The replacement is part of plans to improve train reliability.
Giving an update less than a year since the Committee of Inquiry released its report on the 2011 December disruptions, LTA and SMRT said measures, such as real-time detection of defects, have already improved train reliability on the ageing lines.
Both the rate of trains being withdrawn from service and the number of disruptions of over 10 minutes have declined.
However, delays of more than 30 minutes continue to be a concern. In the first three months of this year, there were two such delays compared to three for the whole of last year.
LTA's chief executive Chew Hock Yong explained: "Sometimes, the longer disruption is because a particular train on our network has stopped working, the motor does not run, and therefore we need to, the operator SMRT needs to, deploy another train to physically push out that train, and it takes a bit of time to do so, sometimes it takes longer than desired, and therefore maybe there are."
Mr Chew continued: "Some measures that we can look at, maybe in terms of engineering or operating procedures, to see how this can be done faster, so that the recovery will be faster."
The power rail will also be getting an overhaul.
Both LTA and SMRT are in the process of formulating a plan to replace the third rail system. And to expedite replacement works, the third rail replacement programme will be coordinated with the sleeper replacement programme.
About 35 more trains will be added from 2014 to 2016 to facilitate other upgrading plans.
SMRT's CEO Desmond Kuek said: "The new trains that we will bring in will help us to, first of all, boost the availability and this will be particularly helpful with peak period travel. With the new trains coming in, it will allow us to pull out some of the older first- and second-generation trains so that they can undergo the much needed overhaul programme, so that we bring about a much higher level of reliability and availability in the longer run."
The depot in Bishan will have three more maintenance tracks by 2015 to ensure repair works can be done at an optimum pace.
- CNA/fa