So, I'll speak to what has been done, and why, based upon my own perception and training.
It starts–as everything in our branch–with the djurus and langkas. We have Pendekar Paul's interpretation, but he wasn't the only de Thouars and de Vries student of the art.
In Paul's teaching, the djurus are started with hips and shoulders aligned and facing forward, with the hips "corked," in a front stance.
In the new interpretation, the beginning stance is an open-horse. (Classic horse stance is as if you were sitting astride a horse with your feet in the stirrups, i.e., feet parallel and at a ninety-degree angle to an opponent to your left or right. The open-stance version angles the feet outward, closer to forty-five degrees.)
Obviously, if you get into a sudden fight, you start where you are, and you don't try to get into a stance to deal with actions that are moving too fast to allow it. Stances are transitional, you don't pose there like Bruce Lee for the camera, you move through them, but we are talking about the djurus here.
Kind of like the old joke about karate players who trained barefoot holding up a hand to an attacker and saying, "Wait, wait, let me take my shoes off ..."
So, why change it thus?
Guru noticed, in old photographs of senior players, that they used this stance. He started with that, then retro-engineered it: Why would they stand this way? Why didn't we do it now? Did we find something better, or did we lose track of it?
He talked with and watched seniors in other branches, looked at what they did, realized what they had–and what they didn't have.
This is the mark of somebody who is skilled, and who can connect the dots.
What he understood is that this side stance protects the center better against an opponent on the line of the lead foot. (And, I suspect, that you can also alter your aim to face somebody on the opposite line without having to move your feet.)
Not that you can't cover your centerline in a front stance, but that the front stance needs the back-up hand more to do it. You can throw up a shield with the lead arm against somebody out there and enter. Entering as you face forward gives them a bigger target. Following your lead shoulder in with your shield up is safer.
The side stance is stronger, and it takes a lot of stress off the knees when you drop lower, a good thing–speaking as somebody who has had knee surgery.
Once you enter, then the front stance is effective; you can turn and cork, to deliver a stronger, hip-driven attack, your center is at less risk because you are already in and past a lot of the opponent's tools. So that's not being thrown away, but used when it is safer and more effective to employ.
This is reflected in the new djurus. Learn this with the first two, and you can alter the rest likewise.
This doesn't violate any principles. New students won't have a problem. Old students? It does take some practice to switch to, after doing it the other way ten thousand times. When I first saw it, I confess I was somewhat skeptical. After trying it? I can see why it is better.
The basic punches have been refocused and altered to suit the new structure. The Djuru 2 highline punch is now delivered with the fist held closer to an anatomical-chart position.
Anatomy charts show somebody with their arms hanging down, palms forward. From this position if you raise your arm straight up and make a fist, you'll be in the new position.
What this means is the angle of the arm and wrist is such that the palm is upward, and somewhere around forty-five degrees–halfway between a flat-punch and palm straight up. Looks something like a stretched-out uppercut.
Structurally, a twisted punch is somewhat less mechanically-sound than a flat punch, which is a little less so than the upward-45 punch. You can see this by how the radius and ulna align with each other as you do them. Bones parallel are a somewhat-stronger structure. There was a researched article about this in the Journal of Asian Martial Arts a few years back.
Lowline punches will generally be done with the palm down. Centerline can be done either way, or flat.
Pretty much that's what you'll notice if you see the new forms demonstrated. The changes do ripple through everything, but position and timing and distance are all still there, mostly it's position that has altered. Once you start getting used to it, you can see why it's better.