Find the deployment Mig-31 weird. It is interceptor designed to shoot down low flying bombers. The Su-25, NATO code name Frog Foot, is dedicated ground attack craft; the Ivan version of the A-10.
They are thinking of “you know who” to the south of Syria. Imagine the regional anal sphincter factor when Russia decides to “temporarily” occupy the Golan Heights as a “tactical measure to interdict terrorist supply lines” or other such”canards”!