Hi from a fellow Bulldog owner. They have a very dominant protective streak and they are very demanding. Thankfully so very very cute as well. They are fast learners and my Bully learn't faster than any of my other dogs where to toilet and when. Oscar is almost two and learning to sleep past six is simply an age thing for most dogs i think. If you have a space for him that is his space he should quickly learn. Make sure you do get up and let him out for the toilet even if after that you put him back to bed and if he keeps barking just stick to it. They like their sleep as much as we do, barking won't last long