The TR7966 is the first train of the day, arriving at 6:08. The latest train arriving before 16:45 would be the TR9427 arriving at 16:08. Would you prefer that?
Do either of those trains depart from Cambridge? I'd like to leave from there if possible.
TR7966 does depart from Cambridge and arrives at 6:08. The latest train from Cambridge to Stansted airport on Thursday arrives at 10:10. It is train TR6242. Which do you prefer?
The 10:10 would work for me!