Sounds like there have been quite a few recent changes in your kitty's life that may be contributing. The fact that he goes beside the boxes tells me that he doesn't object to the location of them, but something to do with the box itself (ie the type of litter, the uncleanliness, the size of the box, etc). It could be that Ozzie decided one day he didn't like something about the boxes and now he's gotten in the habit of going outside them. Your mission, should you choose to accept it, is to make the box as appealing to him as possible, so he remembers the joy of a good pee in a nice loo.
I would for sure pick up a bag of the Dr. Elsey's Cat Attract litter and try that, along with scooping the box twice a day. I took in a semi-feral kitty that probably had never used a litter box and the Dr. Elsey's worked like a charm. Also, a Rubbermaid under-the-bed storage box makes a fabulously large litter box, way better than most the ones you find in pet stores.
Good luck!
