This is an entirely normal part of puppies growing up. He is at the stage in his life where he is really starting to understand that his own behaviour can shape and influence the world around him.
e.g. If I bark = humans get up and life becomes more exciting
This will not be the last 'naughty' behaviour that he experiments with.
If you are sure he is barking to wake you up then you need to break the connection in his mind between barking and humans turning up.
There are multiple ways to do that but with battendog I used an alarm. That alarm was set earlier than he would wake naturally and we had a simple rule:
- nothing of value happened before the alarm went off; it didn't matter if I got up for a wee or let him out for a wee or moved about or whatever. If the alarm had not gone off then the day had not started. If I went for a wee he was ignored. If he needed a wee he was taken out into the garden, wee'd and put straight back into his crate and ignored. If I moved about, he was ignored.
- the day only started when the alarm went off. That was the signal that we were getting up and walks and playtime and food would begin.
When it was clear to me he really did understand what the alarm meant because he never got excited by anything until the alarm went off, then I started to sneak it back from 5.30am to 5.35am to 5.40am and so on - until it was at a decent time.
Now he's an adult, the alarm still signals the start of the day but I can switch it off at the weekend and he just snoozes through until I get up (it helps that get up quite early but have, on occasion, slept in until 10am wthout bother).
Pet plug ins won't make any difference to this circumstance because they are not sedatives (not that I think sedatives are the right answer either).
Black out curtains and whte nouise may well help because they will reduce the outside signals that the day has started. I would imagine by now he has started to learn the radio schedule - e.g. when the presenter's voice changes from Vanessa Feltz to Chris Evans then it must be time to get up
. Setting the radio on a timer to come on at a certian time in the morning could work like the larm clock above, if you set it up that way.