i am needing help with your train schedules .
user
what is your planned itinerary ?
assistant
i will be departing from birmingham new street and arriving in cambridge on sunday at 18:45 .
user
what time do you want to leave by ?
assistant
i would like to leave no later than 19:30 .
user
there are no trains that match your criteria . can you verify the time you want to leave ?
assistant
i do not care what time it is leaving but check again for it arriving by 18:45 .