Write a continuous route between the two doors
For a lesson ending at four, note when the participant can actually leave the room. A changing room, ten-minute walk across a large site, or queue at the exit can matter more than a nominal driving estimate. At the destination, ask whether four thirty means arriving outside or being seated inside. Work backward from the correct finishing point rather than treating a map estimate as the entire transfer.
Check the minutes that are missing
Suppose a lesson ends at four and a meeting starts at four thirty. The drive takes twenty minutes, but collecting a coat and finding parking takes another fifteen. Move one commitment or ask someone else to make the trip. A reminder cannot recover the missing five minutes.
Choose a fix that changes the arithmetic
With only thirty minutes available for a thirty-five-minute transition, identify which part can move. Could another adult meet the participant at the first door? Could the meeting begin ten minutes later? State the change and check the revised times again. If there is only a five-minute margin, ask what happens when the lesson runs over. Choose a different arrangement when even an ordinary delay would make the second commitment unreliable.