My puppy is so bitey!

I have a four month old cockapoo puppy. I know that puppies can be bitey, particularly when they are teething badly.

I know that a lot of his biting is likely teething related, as we are often able to redirect him to a chew and that sorts him out.

But our main problems are –

He suddenly goes in a rage of biting, particularly in the evening when we are on the sofa (I suspect a chunk of this is tiredness even though we try to be strict with enforced naps through the day)

But he particularly leaps at our arms and my wife's hair relentlessly.

The second is he still continues to bite when we groom him and put his harness on. Despite him having them as daily experiences and we reward him with treats when he has moments of not biting.

He also went for his first proper groom last week, and the groomer said he was pretty bitey.

We've been focussed on getting him sleep, redirecting him to things he can bite and chew, and the technique of ignoring him immediately after a bite.

He has got better in some aspects, but it's still quite intense. Especially in the evening when we try to relax with him on the sofa. We wouldn't mind as much that he can't settle outside of the pen for now if he wasn't trying to take chunks out of us every second were sat with him.

Equally sometimes stroking him or nudging him into the right direction, or putting his lead on can quickly turn into a bite.

(just as a note – he's nowhere near as bad when he first gets up in the morning, so I suspect sleep has some involvement)

We are getting a dog trainer visit in a couple of weeks that we aim to talk to about it.

But any tips appreciated!