I havent been able to track down a release date
paulmilbank: Samsung have little to no investment in WP at the moment. The Ativ SE has not even got 8.1 yet and it was released in the last month or two. Apparently there is an ativ core coming which will release with it, but that is not confirmed yet and looks to be mid-low rather than high end. Still, even the lumia 920 doesn't have it yet, and that was the flagship at the same time as the Ativ S.
I think Samsung would rather can the update to 8.1 though if they can, I doubt they want to be putting resource into supporting a 2+ year old phone that they didn't sell many of.
I understand that you would like to know to when the new firmware will be released for your Samsung Ativ S.
At this time we do not have a confirmed time frame to release the update you mentioned although we are looking at end of August but cannot promise the actual time and day. Our product teams do evaluate software updates for mobiles on a continuous basis and we aim to make important updates available as soon as possible.
There is a lot of work involved in development and testing to ensure the software works optimally for Telecom users. For this reason critical updates are prioritised over non-critical updates and in some cases non-critical updates may not be released.