why suddenly got 3 brbp buses do sv143, i thought all the while
is 2 buses?
All outside schedule. Meaning extra buses to beef freq (or rather
maintain freq due to jams in Orchard) on the service. Buses report
to the interchange timekeeper and wait for further instructions to
start trip whether full route or downroute.
In addition, they cant be detected on the iris system as its not
a scheduled trip. So if you are in orchard and the arrival board
reads 4 / 35, you better hope there's an outside schedule bus
inside somewhere in between if not if you miss the 4min one you
have to wait 31min more for the next one.
