Hi there,
My Lab/shepard mix completely tunnelled out the entire back yard of a house I was renting years ago. From 3 to 10 months old, he decided he liked to make "dens". :rolleyes: It was worse than having gophers or prairie dogs. It looked probably like the surface of the moon with all of the holes and tunnels :) The deepest one was 20 feet long. A friend crawled in to find out :rolleyes: Before we moved, I had to have a truck dump about a half ton of dirt to make the yard safe again :)
I stopped him from digging only by crating him in my absence. That worked quite well. I'd give him a break about halfway through my shift. So he'd sleep while I was working.
It wasn't from boredom, he really loved to dig. I would take him to the river shore beach about once a week where he could dig his heart out. He was happy and the new place remained intact. Because of circumstances beyond my control, he only lived 3 years--or so I believe. So I cannot say if he would have ever outgrown this.
You can try to stop it completely by making sure your dog has no chance to dig. Or allow her to dig, but control the action for place and time. For some reason, schnauzers have "digging fits" in my family. My parents supplied them with a 2X2 carpet remnant for their short frenzy. :D
As for the biting instead of licking --- imo hands/body parts are completely off limits to any mouthing by dog. If it occurs, firmly discourage it.
Saying "no" and isolating her usually will work in time. Or you can train her to keep a toy in her mouth instead of trying for humans :) Just a couple of ideas. :)
It's up to you how you want to try to deal with these two 'issues.'
hth and good luck,
toodles

BTW, on the licking/biting problem, don't confuse the dog by making it "ok" for play and then "not ok" at any other time. She's too young to differentiate. Perhaps when she gets older it will work out, but not while she's a puppy.
Labs are supposed to have 'soft mouths' so chewing on people and their hands is a no no. It's a natural instinct to start out by licking...so that could be a sign that she's about to use her teeth.
best wishes 