When it comes to Cattleya maxima, they are all judged as Cattleya maxima! We don't distinguish between the two.
However it is generally said that the upland plants generally produce 3-5 flowers and they tend to be of darker color and better form.
Flowers of lowland plants number between 12-15, are more floppy and tend to be from white to pink with darker veins in the lip.
In looking over recent awards, we find a clone, 'Chadwick's Dark'. It had five flowers on a single inflorescence. I think we could assume that it was an upland clone. It received an AM of 86 points!!
That was in February of 2018.
If I look at an award from 2013 to 'Peruvian Beauty', I would assume that it was a lowland clone. It got an 82 point AM with 36 flowers and one bud on two inflorescences! I see the color to be a medium pink/lavender.
The color of Chadwick's Dark was described as being pink, overlain with darker pink!
No where in the records of awards could I find any reference to lowland form or upland form.
Any judge worth his weight in salt better be familiar with the differences or be good enough to discover them while doing research. No maxima should ever be screened for low flower count, say 4 versus 12 because it could be the upland form where the flower count would be proper.