Point of reference, we were on J award tickets from Lanarca to Malta. Expert Flyer showed F3 the morning of our flight. We showed up at LCA right when the ticket office opened, agent looked our tickets up and said we could not upgrade a mileage ticket with miles. I called the main line and the agent on the phone said the ticket office had no idea what they were talking about and to check with both the check-in counter and on board.

Check-in counter opens, immediately confirms our upgrade for an additional 13,000 miles.

Unfortunately the plane was only 15% full so we boarded 15 minutes before departure time and were pushing back from the gate 13 minutes later. Fantastic flight with the normal exceptional crew, purser was from Malta so got lots of tips.