My husband is like this, and I left him on his own with our baby for a weekend in July. They were all good and he did sleep lighter because I wasn't there x
In my experience he wakes when Im not there, they subconsciously know they are on duty x
Following as I'm in a similar boat. Not working nights but I have a birthday weekend away planned in a few months and my partner similarly never wakes up. My mum said he'll sleep different and more light while I'm away but would love to hear others opinions x