I can give you my experience with EVA with a badly delayed flight. My flight out of YYZ to TPE was badly delayed last year. Everyone knew that we would miss our connections at TPE. I was on business out of YYZ to TPE and PE out of TPE to BKK. They had 15 hours to make new bookings but when we landed in TPE, at the transfer desk they did offer us the option of flying in Y to BKK as the only option available. But we all had to go the transfer counter to do that and get new boarding passes for our new flight. One pax who missed his flight to CEB, they gave him a hotel and booked him on the next day as there was no connections.
As for telling passengers there are no seats it is a bit surprising but was it after they closed the flight or before that? They may have a book load of a full flight if the flight was not closed still. Normally I find EVA fairly good especially with the business class or their G members even at outstations.