I figured this would happen and I think in the long run BioWare wont do or say much about it. There won't be an apology nor ending changing DLC. At most they'll deflect criticism while pretending they 'understand' how fans feel but felt this was the most fitting end for the franchise.
You just have to look at the Deception apology to get an idea of what they'll say. They not once implied they were apologetic for the fact the book was fucking awful, only citing 'errors' and 'oversights', aka the concrete stuff you can really pin them on. You cant really argue against huge lore fuck-ups, hence the apology. But ME3's open ended whimsical bullshit ending doesn't really fall into that trap.
Yeah, I actually kinda forgot about Deception, they've released no new info at all about it, have they?
I don't honestly understand the whole "we're waiting for more people to finish the game before we (Bioware) will actually step into the discussion and discuss the ending with you guys" argument that Bioware is using as their justification for not commenting unless the above holds true. The ME fans have beaten the game by now, except maybe in Asia, where the fans would probably be beating it by this weekend, and they're the ones who have gone out of their way to comment on their dissatisfaction with the endings. Bioware either:
-has had a plan all along (I think the craziest theory I saw was that due to mass indoctrination, enough people world-wide had to pick the destroy ending and submit that data over the internet to Bioware's servers for the indoctrination to break). This is giving Bioware far too much credit, especially with the Final Hours app. Although, they did state they were experimenting with indoctrination in the final sequence and only dropped it because losing all control of Shepard would be too weird for the fans, so SPECULATION.
-or that they have absolutely nothing, and are trying to let the internet hate machine wear itself down before releasing a statement that says "ending DLC (maybe) coming soon, in the meantime, buy Omega DLC and finish Aria's story! You also get a new multiplayer map!"
In either case, the longer they wait, the more fans they are going to risk losing.