I had an injury late this past summer that pretty much left my Wine and Dine training down to 2 weeks! haha The thing that is nice is that you don't have to run if you aren't able or conditioned to. It may not be the race you planned on but it'll still be fun! I haven't done races very long and 100% remember the time before the first race when you're certain you'll not be able to make the pace requirements. But it can be done just walking fast. That's what the Balloon ladies do - they don't run!
Being at a "only" 4 mile/run walk in October was well ahead of the curve - you'll be fine. The Galloway suggested training is just past 2.5 miles at this time.