Windows Phone 8.1 Update 1 in the Preview version aimed at developers just received a new update, which it seems it does not bring anything new, and only going to correct any errors. There is no official announcement.
Updating Windows Phone 8.1 Update 1 v.8.10.14157.200 reaches and the truth is that it is not too big and so it has been told so far not bring big surprises. Not even corrects any errors that remain outstanding for an upcoming update.
So they have announced from the company is still working to fix the bug that prevents some users to upgrade to Windows Phone 8.1 Update 1 in the Preview version. When informed of these developments.