Planned tentative meeting with potential client, I'm planning to book refundable First class Delta ticket (Class P). If meeting is cancelled, I plan to fly back home on already confirmed ticket with another airline.

1. Flight is at 7.30 pm and I plan to cancel it by 3pm depending on response from client - Is P class full refundable?
2. I'm currently TSA pre-check member, I never booked 2 flight tickets leaving from same airport on same day in matter of 3-4 hours- will TSA question about these 2 flight ticket booked?