Late last Friday, the new signalling system on the North-South Line received a software update aimed at ironing out some of the "teething issues" that have cropped up since full-day tests of the system began in May.

Developed by French company Thales, the update is expected to improve trackside-to-train communications and strengthen the signalling system's main server.

The fix spells a possible end in sight to the delays that have plagued the 30-year-old MRT line since full-day testing started two months ago.

In addition, the system is that much closer to delivering on its promise to enable trains to run closer together, resulting in shorter waiting times and less congestion for commuters.

It has been a long five years since upgrading works first began. However, commuters may not be able to enjoy uninterrupted journeys just yet.

Rail operator SMRT and the Land Transport Authority say it could take up to a year for the new signalling system to stabilise, going by the experience of metro systems elsewhere that have gone through similar re-signalling projects.

Commuters may also have to wait several years to enjoy the full extent of improved services on the North-South and East-West MRT lines, as other upgrading projects are still in the works.

These include the replacement of the third rail and power supply, as well as the replacement of 66 ageing first-generation trains and the introduction of 57 new trains on the two lines.

Still, the software update will go some way towards assuring commuters that their frustration is temporary, and that the $195 million spent on upgrading the signalling system of the North-South and East-West lines - the two oldest MRT lines, forming the backbone of the Republic's rail network - has been worth it.

As the MRT network's daily ridership continues to increase, hitting 3.1 million trips a day last year, it is essential that efforts to improve rail reliability remain on track.