but I have concerns about my dog since she is out of the 8wk-8mos puppy age range
Dogs aren't robots, and they don't know their own age. They don't wake up and say "hey i'm 8 months old now.... i'll change the way I interact with everyone"
Some dogs mature quicker than others. I generally see a change around 10-11 months old, but every dog is different. My pups are only just now starting to show any signs of maturity and they are coming up on 16 months old.
the usual methods of teaching her a soft bite (i.e. the high-pitch yelp, redirecting with a toy or bone) have not done a thing.
Yanno, this high pitched yelp stuff always makes me chuckle. Maybe it works with some dogs, but any dog that has enough character to be "barking, snarling, growling, lunging, and jumping in a frenzy to try and get her teeth on any part of you that will stand still," is not going to respond to yelping.
Redirection, however, is good. But redirection is an art -- most people reward the dog, rather than redirecting the dog. I wouldn't give the dog a bone either, give them something they can tug on and use as an outlet for their pent up drive.
I also do not think this is an obedience issue, as we have gone through puppy kindergarten and basic dog obedience classes, which has taught sit, stay, down (not so much heel...she is a puller and walks much better with the EZ Walk harness than a flat collar).
I would go to a gas station and fill up a small container with gas, put the gentle leader (which I assume is what you mean with EZ Walk Harness) in a metal can, douse it with gas and burn it. Then teach your dog to heel properly
The puppy classes and stuff like that are not very intensive classes, and they shouldn't be, because the dog is young at the age you bring them to those classes. I would read all the articles on obedience training that are available on Leerburg and follow those. Of course, your dog is still young, so don't expect too much from him at 8.5 months old. The dog is very much still a puppy, they just get big pretty fast.
OK, the biting issue. Redirect the biting. Learn the dogs body language and predict when he is going to start behaving that way, and redirect before it happens. If the dog interprets your redirection as a reward then the dog will keep acting that way in hopes of getting rewarded for it.
With the frenzy behavior, you need to be extremely consistent here. I would handle it in 2 different ways.
Firstly, you need to be consistent. If you are in a situation where you are unable to focus all your attention on the dog, then the dog should be crated. If the dog "sometimes" gets to do these things and "sometimes" not, then the dog won't understand what you want. If the dog starts to get into a frenzy, then crate him immediately each and every time.
The alternative, and probably more along the lines of what I would choose to do personally, depending on the amount of time I have available when the dog starts going nuts, is channeling this behavior into something productive, like obedience.
A lot of people see obedience as a way to control the dog. This simply isn't true. Obedience is being able to work with your dog and enjoy an experience you share with them. When I say channeling it into obedience, I don't mean "tell the dog to lie down so they aren't annoying." Instead, grab some pieces of hotdog, cheese, kibble, whatever it is you use to reward your dog, and use the dogs behavior to your advantage. All that barking and going wild in a frenzy is the dogs pent up drive coming out. If you channel this pent up drive into another drive, such as food drive, you can then have fun with the dog by working with them. Practice his sits and downs, teach him a new trick. Teach him to shake paw, crawl on the ground, sit up etc. If the dog is channeling his drive into thinking about these things, then he isn't biting you or going into a frenzy, and you are then also doing something fun with the dog which also changes your perception from: "this dog goes crazy and drives us nuts," to, "it's really fun working with a driven dog that loves to learn new things."
I personally love dogs that go absolutely wild, because they are the most up-beat, happiest, driven dogs. That is exactly the type of drive and enthusiasm you want from a dog in order to teach them new things.
Also remember that there is a puppy witching hour right around 8pm, where dogs for some reason like to charge around the house like maniacs before going to bed.
Exercise the dog more too, although don't overdo it on hard surfaces as the dog is still young. But a tired dog is a happy dog that is less likely to go into a frenzy in the first place.
Good luck, enjoy your dog!