As a non-expert, IMO the most important thing is to NOT be at/over FTP at the start. Every time I’ve failed one of these it’s been from biting off more than I could chew. It should feel like sweet spot in the first ten minutes, then kick it up a bit. For me there’s a ‘not nice but bearable’ burn in the legs for most of the test, and the clue I’ve gone over FTP is breathing rate changes from fast but controlled to ‘gulping’ air.
I’ve got some workouts here, you’re welcome to join and try one of them:
The thing to bear in mind is that these have been modified in order to get a small FTP Increase, so if you’re doing them as written you’ll probably want to start off with an FTP set to 220-225. You can always double check what the targets will be and increase/decrease from there.