"This competition requires participants to predict travel time on Sydney's M4 freeway from past travel time observations". This line seems to suggest that the past travel time is the most important part of the experiment; however, as one other (rrrhys) pointed out, the data is useless, since the road has changed, and the grandparent of this post mentioned sporting events affecting traffic.

All of that said, perhaps a strong model can be generated using just historical data.