Don't give up hope! My Zeus' ears were floppy until just recently and he is two and half years old! They have been standing up more straight now than ever. It's rare, but definitely possible his ears could rise later in life!
Haven't necessarily given up hope, but I have quit stressing over it. He is a gorgeous black and tan, and he is huge! He is about 60 pounds already and a big baby....It would be nice if his ears came up because he is so beautiful, but taping and gluing have been so stressful....I want a happy dog.
I am gluing my foster's ear and he's a year. My breeder once had a 9 year old's ear go up after being supported by a cone for a few months - not something she expected! I think I would have a harder time doing it if he didn't like it though - he just doesn't care about it. His other ear is up, but soft.
My flop-eared baby brought his food bowl in the den and dropped it in front of me...first time he has ever done that! I waited a whole 30 seconds, then got up and filled his bowl...pupper needs to know I am the boss!