What if someone began a trip before the Nine Days and now wants to return. Is he allowed to, in light of the prohibition against doing dangerous things during the Nine Days, including travel? Does it make a difference if he began the trip during the Nine Days, against Halacha? Does it make a difference if he's looking for a loophole in the Halacha, versus if it just worked out that way unintentionally?
In any event in which he may return, is it better if he went to his destination by car to return by plane, which is both faster and safer?