My DS2 is 4.5yrs old. He is very wet in the morning. I use pull ups at night, no choice really. I also have a Connie/Kerri under the sheets in case he wets through the pull up.
When we start to get serious about night training, I will use (as I did for DS1) the Connie/Kerri on top of the sheets so I don't have to change sheets. I have two so I can change them and not have to worry about them drying after washing straight away.
You need at least 7days without a wet night before, you could try doing the lift to the toilet before you go to bed, It may work?
My DS1 didn't stop wetting at night until he was 5.5.
It's very normal, frustrating I know, he will stop one day.