Here is the full statement from SMRT:
To facilitate the continued acceleration of the power cable change currently undertaken by the Land Transport Authority (LTA) and SMRT, some service changes will take place on the Circle Line (CCL) on two Sunday mornings in May 2013.
On Sunday 12 May, Marymount and Caldecott stations will operate with a single platform from 6 to 10 am. Trains going in either direction will stop at the same platform, as the other side is closed to enable cable change works.
A similar arrangement will take place at Botanic Gardens and Farrer Road stations from 6 to 10am on Sunday 19 May.
During these periods, there will be signs put up at the affected stations to inform passengers of the change in the platform arrangements. At the same time, we will be making announcements at the stations and in the trains, to alert passengers of the diversions. We will also deploy some of our staff to guide passengers on the ground.
Passengers may be inconvenienced with an addition of up to 10 minutes in their travelling times. We ask for their understanding, and advise them to adjust their travelling times accordingly.
I tot usually such maintance work is done midnight de?
Replace power cables....this one is very chor gang, and also must chop-chop do before something else happen and people chop 3-star's head off.