I looks like you've always had the same basic issue, which is that you're pinching with your knees, which lets your upper body get too far ahead, which is why you're resting on your hands over the fences. It also looks like you duck over the fences - that is, you get too close to the horse's neck with your upper body. In the first picture from three years ago, you can see how much this destablizes your position - you've fallen back on your horse's back over the apex of the jump, because you don't have a position that will allow you to hold yourself up in two point.
The suggestion of riding a lot in two point is a good one. I'd also suggest practicing things like holding your arms out to the side while in two-point (probably safest to do this on a longe line). You can also do it over fences, if you're working through a jump chute. When riding in two-point, make sure you're not resting on your hands. Even if you can't get someone to longer you, try holding your hands low and wide, away from the horse's body, while in two point. When jumping overwise, I'd recommend putting a braid in your horse's mane and making sure you reach up to grab the braid over each jump. I'd also advise getting into your two point a couple of strides before the jump and then focus on just holding that two point and letting the horse jump up to you. This should help stop the ducking. Different imagery works for different people, but you might try thinking that you want to "hold your shoulders" up over the fences, or even that you want to "wait for the back feet" to jump, so that you don't throw your body at the fence.
Good luck with your riding!