I think BA is in a spot of bother and confusion itself about the release date, and the delay of Ashes has caused this phenomena.
In my opinion, an August release would have been better. Considering the current situation, I guess Big Ant HAS TO release the game before Ashes 2013 hits the market. The reasons are numerous.
1. If Ashes Cricket 2013 comes out earlier, no matter how bad the reputation has been, don't deny the fact that it WILL sell some copies. And hence, it will consume the cash of general public.
2. If it turns out to be great (highly unlikely though) it'll damage DBC'14 more than anyone's expectation. On the other hand, if it turns out to be awful (I guess because of BA's competition and all, the game will be significantly better than Ashes 2009 and IC 2010) then it will leave a bad impression on general public regarding cricket games. Not many people will invest with the same amount of enthusiasm anymore in DBC'14.
Don't forget that if BA decides to go later than Ashes, it will be targeting a late Nov or early December release. And by that time-frame, the fever of Australian Domestic and Ashes will be relatively over (if I am correct about the fixtures) and the gamers will already have the following games at their disposal:
1. GTA 5
2. FIFA 14
3. Batman Arkham Origins
4. Watch Dogs
5. Raven's Cry
6. Assassin's Creed 4 Black Flag
7. Battlefield 4
8. COD Ghosts
9. Ashes Cricket 2013
10. Forza
P.S: The next-gen consoles will also be there and BA will be releasing a game that will be for 'old-generation' consoles by then.
If I were to decide, I would have gone for an early October release. Only GTA would've been there to compete with and AC & Batman are in near-sight. Ashes would be literally 'dumped' in its coffins because no one would purchase it by the time it will release. People are hungry for cricket games and whoever comes first here, will win the race!
Best of luck to BA!