On the main site for the show, they already listed the Volume 1 of the BD/DVD which has one episode (and Vol 2-5 will have 3 eps each). The interesting part is that both the BD and DVD lists the episode as "Stage 1 Director's Cut ver" plus it says the actual episode is 27 minutes long. This means the BD/DVD version will be around 3-4 minutes longer than the TV one.
My guess that extra time will be one extra music on the concert at the beginning, after the end of Aitakatta and before the enemy forces arrives.
Now I wonder if all episodes will have some extra minutes like that. On Episode 4 for instance, would be nice if we are to see the full Heavy Rotation at the beginning of the episode, instead of just seeing the start and then skipping it like happened on the TV version.