Anyway, I think BNDEP has started to fix some of its SP buses
(especially the Mk4s) as replacements for its last few outgoing
Mk3s already. Like 2833B running around with NETS ad, 1930K with
new rear Meiji ad.
Just that the in-house implementation date of their fleet updates
are likely set internally to only come into effect on the day after
the officially de-reg date of Mk3s, that's why you don't see these
buses yet on the services to replace the Mk3s. Also cause BNDEP has
the practice of using its dereg-ing buses till the very last day of
its lifespan, unlike HG & AR/BB which lays up many of their
Mk3s way before de-reg date. That's why some slots like 879H's on
358 are constantly being covered by cameos this week. On the days
879H did 45 & 15 in the past week, 5039H covered for it on 358
for example.
That's why I wouldn't be surprised if 6185L is perm 229 after
852J goes off these few days cause it has been stuck there for
ages, but rotating around different slots on 229.
Had the same thought as you on 6185L eventually replacing 852J
but did not turn out that way. Maybe BNDEP prefers to have at least
1 non wab bus for each feeder services (as with 225, 228 and
292)
Wonder if the 2 citaros on 292 is the same case with 6185L
(appearing daily but not perm)