Mercifully, an A seat became available in second cabin. khap khun krap

eta. And today the vaunted 19A became available. unfort, had to become a pseudo coder to access the seat selection feature on TG website/app, as it was a star alliance partner leg and they notoriously make it difficult to do that, but thanks to reddit was able to do that too. why you need to follow the seat map like a hawk!