Yes, svc 23 used to travel all the way to Orchard Rd, but I'm
not sure if it looped at Tomlinson Rd. However, it was later
shorten to loop at Rochor Canal Rd, coz the MRT line was opened
between Tampines and Orchard.
Yes, Mercedes Benz MB O405 (eg SBS484M) later joined forces with
the existing Scania N113OACs to serve svc390 (but no sure abt Volvo
MK II deployment on this svc).
Svc 16 also uses a number of Scania N113 CRB and OACs during the
route from Bt Merah-Airport. but most of the fleets on this svc are
dominated by the Volvo families..