Yes. 988Y's configuration is a puller bendy (due to the mid engine
config of B10M) while 999U, like most O405Gs the configuration
is a pusher-bendy.
Due to the B10M bendy mid engine configuration, the rear
axle at the trailer could turn. But the disadvantage was that the
people in the trailer of the puller bendy can experience some
unnatural G-forces when turning.
B10MAs can have the option of steered rear axle or fixed
'dual-tired' axle.
Its not neccessary that people in the trailer of a puller bendy
to experience unnatural G-forces when turning. That only happens if
the bus turns at very high speed. Besides, no one should ever turn
a bendy at high speed, akin to driving a container trailer. The
steered tag axle is there to help a puller bendy to turn better in
tight areas, but having a lower capacity.
