Our society generally grades people from unranked to 5th but does the kata for 6th (ai hanmi) at the same time, I know of one dojo in the society that does 6th though, and throws in weapons and randori for good measure.
When my wife and I did our 3rd kyu we had a guy with us who was ungraded but had trained in various dojos in various countries for a couple of years, never in one place long enough to grade due to his work. He didn't know any our kata/syllabus but his ukemi was lovely and his grasp of basic techniques and principles sound (so far as I'm any judge). Sensei asked him how long he'd been training and then just said "you better be 3rd kyu as well then" at the end of the grading, smiles all round.
Krystal, nice one