Just like not feeding your child a meal will make the child hungry, but not in any health risk.
Until child protection comes for you anyway lol (Terrible joke, I know) :54:
Anyway, like it's been said, you can leave the bird for 11 hours, but whether it's an ideal arrangement is another argument, and in my mind at least it is cruel to do so unless the bird is developmentally ready for that kind of time period between feeds. I doubt we can sway your mind. if you chose to go with the pet care facility as an alternative, be aware of the potential of disease transmission (does happen) and incorrect feeding techniques.
On another note, if your travelling, I'd start planning your travel kit and what you will need to make the journey for the bird as smooth as possible. Travel cage, water and food dishes, enough of the water from your house the bird is used to to mix up formula and provide water for the duration of the trip (foreign water can cause issues in animals due to different compound in the water, just like how human kids can have intestinal distress from a different towns water. I'm not sure how this would affect birds, but better to be on the safe side. Alex always prefers home water anyway, I think water from elsewhere tastes different to him.) pellets, seed, fruit (or buy when there) enough formula for the trip etc. Don't forget toys and other familiar objects to comfort the bird in an unfamiliar situation. When travelling with Alex I pack all of these into a carry bag.
Is what out travel kit when half ready looks like (Travel cage, seed and pellet mix, fruit, formula w/ feeding spoon, harness for emergencies, wetwipes to clean up poops, a baggy of his favourite toys, etc). I would in addition to what is visible I also take bottles of water and a bunch of clip on food dishes, (one is visible in the cage) and a few other items. It fits into a calico shopping bag quite well. I don't have toys in the cage while in motion, it's too easy to injure a bird. Well, besides the rope swing because he loves to sit on it while in the car and it can't hit him where it is positioned if he is on a perch or cage wall. All doors are pegged shut because he knows how to open them. he now also knows how to remove the pegs so I have to use dog clip things.