Rebellion has plans to reveal a new project soon, confirms Videogamer, who contacted the developer to follow-up on indications this will be Sniper Elite 4. They did not get that confirmation, but have an image of a LinkedIn profile that mentions the sharpshooting sequel by name. Here's the statement from Rebellion's Jason Kingsley, which deflects, but does not actually deny the discovery:

"To be honest we're flattered that people are actively searching out for a new Sniper Elite title, and we certainly don't mind being mentioned next to projects like Black Ops 3 and Unreal! However the person in question doesn't work for Rebellion and we haven't announced a new entry in the Sniper Elite series.

"Last year we celebrated the Sniper Elite series' 10th birthday and 10 millionth sale, so our IP is still hugely important to both Rebellion and independent UK games development. We're actually gearing up to announce a new Rebellion game soon, so expect to hear more from us before GDC!"