It would be interesting to see why they chose to replace a E5
KUB for a Citaro, when there's still that E4 KUB 8888D still on.
Means most likely nothing to do with mileage but more like BC
preference?
Although I must say 8888D is one of the better maintained Batch 1
E4 KUBs running around now, the other Batch 1s HG used to have all
kena thrown to other West-side district depots if you do realise
(I'm not counting the TRG ones). 
yup ! correct this 8888D The only one batch 1 kub still keep by
HGDEP as for normal svc on 109 as for 8622D this bus were not
seen on 109 as from 1 st JAN 2013 until today and it keep running
around on other svcs and now i think stucking on sv 159B Liao
!