Eight systems is a significant presence, and would allow engagement of cruise missile swarms, as well as piloted aircraft, so a stress test may be a better description, and apparently the S400s will remain in place defending Russians.
The political component might be described as "fed up".
Although much improved, the S300 was deployed in 1979 under the old Soviet Union. It would appear for now anyway, the S400s stay in Russia proper and Kaliningrad.