blade 747
The course can take anything between 3 and 5 months to be on line, depending on Simulator availability and aircraft. There is plenty of time off between various events. If there is a delay in sim you may well find you are sent on forced leave as SQ like to get rid of this whilst you are unproductive.On my course years ago local F/O's who were not able to be slotted into the sim for three days were forced to take these three days as leave!!
If you leave Singapore during days off it will be at your expense as there is no entitlement to tickets until 6 months in the company. Unlikely that you will get enough days off in a row during the training to go anywhere except close by unless it is taken as leave.