A,B,C,D are services from Interchange E
A is a BSEP service
B,C,D are introduced around a decade ago
A is already dual depot when introduced
C,D are single controlled depot
B was once single depot but was changed to dual depot
A,B,C,D share the same depot I
B and D share the same route and both plies the same
neighbourhood F but in different direction and both never meet
again. D used expressway H to go to its destination
C and A share the same road after leaving interchange but splits
at Road G. C and D meet again at Road H and both split again
thereafter and never meet again.
Hint: All SBST service
A= 50
B= 57
C= 58
D= 59
E= Bishan
F= Toa Payoh
G= Ang Mo Kio Ave 10
Road H = Kaki Bukit Ave 1
Expressway H= PIE
I= AMDEP