Improve show_timetable heuristic
Improve show_timetable heuristic

stev-0/bustimes.org.uk,stev-0/bustimes.org.uk,stev-0/bustimes.org.uk,jclgoodwin/bustimes.org.uk,jclgoodwin/bustimes.org.uk,jclgoodwin/bustimes.org.uk,stev-0/bustimes.org.uk,jclgoodwin/bustimes.org.uk,stev-0/bustimes.org.uk