Cat 1, owner 0.
Because your cat has trained you to give him/her attention when he/she demands it at 4 AM, you now have a longer re-training period to go through.
I would simply say "bedtime," stuff in ear plugs and ignore him/her until it time to get up. Try dividing the second meal into dinner and a bedtime snack, to rule hunger out as the cause.
My dogs and cats have adapted to our sleep schedule.
You could also try pushing the response back to 4:30 AM. Once the cat gets used to waiting until 4:30 to start acting up, then move it back to 5 AM.
Skin kids - Jason, Kevin, Allison
Canine kids - Bennett & Bailey (always in our hearts), Riley, Banker, Rogue and Boz
Feline kids - Zoey, Talley and Abra