I know this is quite common in bulldogs due to their shallow eye sockets, their eyes tend to dry out. But I was curious, do you happen you use a powder carpet freshner or any powder cleaning products around him? I've heard numerous stories about the powder/cleaning products drying out the dog's eyes and causing this.
Our Diamond Girl had this, but as soon as we noticed a little redness in her eye she went right to the vet. They suggested steroid drops to reduce the swelling and her gland receded back into her lid. We were lucky not to have to put her in for surgery. Maybe you can ask the vet about a steroid drop to control the problem instead of another surgery