Before these buses disappear from some routes, I've been looking for
information on fleet numbers.
From what I can make out, they are all built by Mercedes-Benz and
externally all look very similar. But why are there several different
ranges of fleet numbers? I've seen MAxx, MALxx, ECA3xxx, EA11xxx and
23xxx. Does anyone have details of the range of numbers for each.

Most of those I've seen have the new format registration numbers, but
I've seen 2 on route 149 that have ex-RM registration numbers, why is
that? And is it a quirk of how these registrations are issued that
within blocks, some registrations are missing between consecutive
fleet numbers.

Dave