I saw this movie recently as well. I gotta say, it's not the best and actually I did get bored for moments. It felt like everything went for too long and it could've gone way faster. I went to the cinema to see a war movie and like you said, we got a prisoner of war movie instead.
And the ending was a bit absurd. I mean who puts a gas container near the wall that would make the whole base explode if it was triggered. Explosions were everywhere but magically it wasn't hit until the Caesar decided to throw a grenade at it.