Last year I booked a 241 Avios redemption LHR-BKK in F flying out in September and returning October. When the W13 schedule came out earlier this year, BA substituted a 3-class 777 resulting in a downgrade of my return leg to J. Now, when I look at my booking in MMB, the return leg shows as "Your e-ticket has not yet been issued, so you cannot choose your seat. Please contact your booking agent". So, I rang BAEC last month and explained the situation. The operator went away for a few minutes and said the booking had been put in the wrong queue but it would now be corrected and had been submitted to Ticketing. However, it's still at the same status and I'm unable to select a seat so I wrote to BAEC today and received an e-mail response claiming that the flights "are all confirmed". Now, I'm no expert but I suspect that Confirmed and Ticketed are two different things and I don't want to arrive at BKK check-in to find we're denied boarding. Are my concerns well founded?