The gearbox seems to shift much higher than I'd expect, even when
gentle accelerating on the flat, it feels like it's in sports mode all
the time. (Even though it doesn't have a sports mode!)

It just revs a bit high and changes late.

I thought there would be a dipstick to check the auto gearbox fluid
level, but there's nothing in the manual(!) and can't find anything on
the web except how to strip it down completely. What would cause this
"lazy shifting"? Low fluid? Old fluid? Weak actuators? And is there a
warning light for low AT fluid? It's been getting a bit worse over the
last 3 months

Really sorry if this is a FAQ, but I can't find "search" anywhere!

Digitaltoast wrote:
your 2nd step after checking the fluid.