Most Marina Centre services loop at either SMRT HQ or at Raffles
Hotel, depending on their route.
The only way to get to Marina Centre area is the Bridging
services. Alight at Stamford Rd (Capitol), walk to North Bridge Rd
and board it.
For services looping at Raffles Hotel would have plied North
Bridge Rd, transfer to the Bridging service at the Bras Basah
Complex stop.
I am rather curious about S195. Where will the place be
for BCs to change shift? 
Edit @ 1540hr: Ok, the press release is out. Understood.