And then bhs to the end of the beam into a layout step out onto a panel mat (put a beam wide line on it the same height). Once adjusted and comfortable with that, like 200 later, start adding one panel fold at a time to increase the lift and height required to make it. I don't think there's any benefit to adding more than two folds, and would spend the kids energy doing them on a padded medium beam from that point on.
If the kid has previously worked bhs layout on the floor line, and done so for a year on a regular basis, it's likely the layout is already as good as it's going to get..... so the added height on the fold up isn't that big of a deal unless it seems there's less energy coming from the kid and she needs a challenge.
Really, the skill isn't that hard once they've learned how to tumble into the take off for the layout. Come to think of it, I've had a few kids tell me they liked the series better than the bhs-bhs they grew up with. Hey, it makes sense to me when I think about the chances of losing alignment when kids go to their hands on the 2nd bhs of a bhsx2 series..... and human bodies are built for feet first, not hands first, landings.