Now that Avengers VS X-Men is over, I presume it's safe to call this promotional image by Salvador Larroca unpublished. This image appeared along with other alternate covers on various comic news websites, but did not appear as an alternate cover for any of the issues. The likely reason is that by the time the series came out, Angel no longer appeared in this costume.
Shortly after posting this, I discovered that this image was used as an alternate cover for Avengers Vs. X-Men #9. The cover image is posted below the promo art. Unpublished X-Men promises more diligence in our fact checking, we stand unwavering against the army of variant covers coming at us from all sides!