From Friday 20 June 2003, the station numbers on the Changi Line will be formally changed.
EW28 Expo station will be changed to CG1 Expo station.
EW29 Changi Airport station will be changed to CG2 Changi Airport station.
Yes, I knew of it about two months ago, when the new signboards for trains was slotted into the holder. One of them had the stickers peeled off, so I was able to gain access to this info.