Thanks for your help.
I took the comment# out of display_rotate=1 and got the screen orientation back to landscape.
I tried:
dtoverlay=hyperpixel4,touchscreen-inverted-x,touchscreen-inverted-y
But that didn’t help.
Then I tried:
dtoverlay=hyperpixel4,touchscreen-swapped-x-y
And interestingly, X in landscape mode is the right way round and orientation. However, if I try adding another line:
dtoverlay=hyperpixel4,touchscreen-inverted-y
or
dtoverlay=hyperpixel4,touchscreen-inverted-x
Both axis are completely wrong again.