Training for touring is unnecessary if:

- you are in normal cycling health
- you are not in some kind of competition, and this can be nothing more than being the weakest member of a party. If you are that, then you have your training set out for you since you can gage what chance you have of making up the difference. The problem is that if they are crazily training flat out for their touring next year, it becomes a bit of an arms (or legs) race.
- If the terrain your tour starts out over is particularly challenging.

Otherwise it is touring, and there is no requirement to be in top shape. You will rapidly improve as you go.