I have to think that the Russians might be hinging on desperation here to start making it's moves before they run out of time. Pretty easy to see that they're testing NATO because they want the Territory from the Baltic States back, and want to push into Poland far enough so they can regain the natural Geographic barriers they had in the days of the U.S.S.R.
They're encroaching on Estonian airspace now, after their testing of drones in Polish space last week.
https://www.bbc.com/news/articles/czrp6p5mj3zo