Richard J. wrote:

[Prompted by this from Neil Williams on the Bendy buses thread:
"To apply the question to London, then - yes, long-distance routes are
better with deckers."]

When and why did this use of "deckers" to mean double-deckers originate?
I had never heard or seen it until I read it on this NG a few years ago.
It's not in my dictionary either.

My school bus driver used to use the term back in the mid nineties (not
in London, mind)