Mighty No. 9 seem to be endlessly plagued with various problems from launch release issues to being just an average game even by nearly all metrics as can be seen in my review here it seems backers of the game, and the game itself just can not catch a break for even a small period of time.
Recently on the Xbox Store, the exclusive DLC bonuses for the $60 backer tier, Mega Xel and Golden Beck, have gone on sale. Much to the confusion of backers who were rightly under the impression that this exclusive content would be for them for backing the game. This appears to have been a decision made by those who run the XBbox Store, though, seeing as the immediate response seems to be that there was never any intention of selling that content and releasing this specific DLC Publicly.
As of the writing of this article, this content is not available on Steam. Also as a backer I have not received any email indicating that this content was intended on being released, there has also been no survey or questions asking if backers would be alright with such a thing via email.
This is not the first time the Xbox Store has made errors such as this one, though. Earlier this year in June those who owned an Xbox One were treated to Fallout 4 and all of its expansions for the low low price of zero dollars. This was corrected shortly after and those who were affected by it were reportedly given $10 codes for their trouble. This mistake was believed to be due to a bug at the time, and it would not be too far a stretch to believe that a similar problem is what is currently happening with Mighty No. 9.