The threshold is 35wpm/175cpm but for each key, meaning the average time between keystrokes should be less than 343ms. You can easily take halve a second and more for an unaccustomed key--say "A", because it's on the left hand and you're right handed and because it's on the pinkie and not on the stronger fingers--but 0.3s and better for the keys you're familliar with, outpacing 40wpm/200cpm. The solution is to ONLY focus on accuracy, be patient and hope for the best.
Set sample length to the shortest possible and skip samples (ctrl+right) if you find yourself making too much errors because you're not focused. Once you manage to type the smaller samples with 0 errors reliably, increase length.
Manually increasing alphabet size is also an option, but I found this to reduce my accuracy and then my speed quickly as it made keys I already knew quite well perform worse just because they were on the same finger as a new key (btw I'm using neo2, "L" made "A" worse because these are both on the left middle finger).