So from reading your post,

What I am understanding is that:

Yellow face
F4 A4 Z3 J7 C7 D7 I7 U3 P0 Y4 B4 H4 K3 M3 L3 V2 G1 S2 N1 T0 X0 E0

This means that there are 4 more tickets to sell for First Class, 7 tickets to sell for Business, and 4 for Economy and that will be 15 total seats open.

Red face.

F6 A6 Z2 J9 C9 D9 I9 U9 P0 Y0 B0 H0 K0 M0 L0 V0 G0 S0 N0 T0 X0 E0

This means that there are 6 more tickets to sell for First Class, at least 9 tickets to sell for Business, and 0 for Economy and that will be at least total seats open.

Green face.

F2 A2 Z0 J8 C8 D6 I5 U0 P0 Y9 B9 H9 K9 M9 L9 V9 G0 S9 N3 T0 X0 E0
This means that there are 2 more tickets to sell for First Class, 8 tickets to sell for Business, and at least 9 for Economy and that will be at least total 19 seats open.

Am I understanding this correctly?
The rest of the letters are just how many seat for each fare class under First, Business, and Economy.
13 fare class for Economy
6 fare class for Business
3 fare class for First