Originally Posted by
jpatokal
It's $8 (and has been for a long time) to book a taxi in advance at a specific time (eg. "5 AM tomorrow"). Booking a taxi by phone is $2.30/3.30 depending on the time/day, but that just gets you the next available taxi, no guarantee that it'll be there by a specific time.
That explains it. I never felt a need to reserve a taxi. Calling right George needed, or having the hotel do so, works perfectly well. If one feels they must be on the road about 5am, I'd be headed out of my hotel room about 4:45am, calling for the taxi just before walking out of the room.
Also, if one has status to speed up check-in, I never worried about getting to Changi more than 1:15-1:30 hours before scheduled departure. Check-in and immigration is generally pretty fast, with status.