Suspect:
SBS9481L
(BN 10) 
(BN
23)
This bus is interesting. Past 3 weeks for Weekdays, I've spotted
this bus more often on Sv 23 than on Sv 10. And Sv 23 is still
missing a bus for the de-reg 1943Z from Wiki it seems?
I think Sv 23 might have
converted back that ASD slot into a ADD slot, cause the demand for
more DDs for Sv 23 is definitely there. Anyone suspects this
too?
Not sure what goes in Sv 10 though. The ADD fleet for Sv 10 has
been unstable lately, ditto for 9519M which has been doing Sv 31
& 65 more than its usual perm for the past 2 weeks. And BN 10
is still missing 1 bus it seems cause 3136Z went to 45 from 10~
looks like sv 10 transfered duties to arbp mid last year, but no
physical buses were transferred then.