According to the rules:
Code:
- BOOK TO CABIN CAPACITY MINUS 1.
EXAMPLE: ECONOMY CABIN HAS 100 SEATS...ONLY BOOK TO 99...
EVEN IF AVAILABILITY INDICATES SEATS AVAILABLE TO
SELL. FULL FLIGHTS OR FLIGHTS WITH ONE EMPTY SEAT
MUST *NOT* BE OFFERED.
- BOOK IN SAME CABIN (SAME BOOKING CODE IF AVAILABLE OR
ECONOMY BOOK H/BUSINESS BOOK C/FIRST BOOK F)
...snip...
2. RSSR MUST BE ABLE TO REBOOK IN SAME BOOKING CLASS OR
H-CLASS.
EXAMPLE: IF A CUSTOMER IS HOLDING V-CLASS AND V-CLASS
IS AVAILABLE THE RSSR WOULD REBOOK IN V-CLASS..IF NOT
THEN BOOK IN H-CLASS. DO NOT BOOK IN ANY CLASS BETWEEN
V OR H..IT IS EITHER THE BOOKING CLASS OR H-CLASS.
Perhaps in the OP's case there was (obviously) no L availability as well as no H availability, although these rules would seem to imply that this could never happen. Is H somehow always automatically available as long as the plane isn't at capacity minus one?
(Admittedly, this copy of the rules is a few months old...)
Bottom line: OP, consider yourself the recipient of the gift from the agent!