I would get in the habit of skipping breakfast, or grabbing something small to go. That would allow you to eat lunch whenever you'd like!
I have never really had any issues with doubling up, because if you think about it you are still digesting the first meal and would still need that insulin, and eating more would still need more insulin so there shouldn't be a problem right?
Is your meal timing based on your insulin levels, or your hunger levels?
A mid day snack wouldn't be to hard if its a sugar issue, or even a hunger issue. Just keep some crackers and cheese at work? or some candies in your pocket for a boast!