题主你好，新加坡F1的官网有详细的介绍，9月14号~16号晚上的地铁City Hall站都会延迟到凌晨：
MRT train services will be increased to cope with the higher demand, with train services at City Hall MRT station extended until 12.30am on 14 September 2018 (Friday) and 15 September 2018 (Saturday); 12.45am on 16 September 2018 (Sunday) over the race weekend.
其它还有一些公交车的信息，官网上都有，这里就不一一张贴了，题主你自己到官网看一下吧：http://www.singaporegp.sg/getting_around。

就这么多，最后祝你在新加坡玩的开心，也请围观我的游记。