Как добраться из Budget Terminal (он же Low cost) в Terminal 1,2
You can make use of the free shuttle bus service available at Changi Airport Terminal 2. The pick-up/drop-off point at Terminal 2 is at the T2 Basement Bus Bay (near bus 36) and the pick-up/drop-off at the BT is between the Departure Hall and the Arrival Greeter's Hall. If you are in T1/T3, you may first take the Skytrain service to T2 for the free BT shuttle bus service. The bus ride between Terminal 2 to BT takes approximately 5 to 10 mins.
The bus ride between Terminal 2 to BT takes approximately 5 to 10 mins.
Ну и ссылка на сам сайт, т.к оказывается у этого терминала есть свой сайт - http://www.btsingapore.com