Am thinking about using the transit hotel at the Singapore Airport. Will arrive Terminal 3 and depart from Terminal 1. Can I transit between the two terminals without leaving the transit area, I prefer to use the transit hotel at terminal 1 rather than terminal 3. I do not want to clear immigration until the morning if I am not able to secure my onward boarding pass with OLCI, then I would need to check-in for my departing flight from Terminal 1