Training for touring is not necessary if you have a basically capable body, and:

1) you can set your own pace;

2) you are going to have enough easy ground to cover, before it steepens, to build up your strength;

3) and/or you don't mind a little suffering. I would rather be a little winded now and again touring, than maintain the fitness level required to meet all contingencies. That would be nice, but my knees won't take it

It is understandable that some folks who like touring, also like to ride their bikes at other times, but it isn't necessary. I know a lot of folks who have done long arctic canoe trips, often a month long, they are not the same folks who marathon canoe, or are members of the dragon boat, or C1 clubs at the bottom of my street. The idea that everyone has to train more diligently tthan a pre-war olympian in order to participate in everyday activities is a pretty recent product of attitudinal changes in the 80s. It's a choice.