rather than so-called Islamic State (IS).
Rhetoric and reality
Russia, of course, has said it is largely striking at IS and al-Nusra "terrorists".
This is another example of the gulf between Russian rhetoric and reality.
But, as Michael Kofman, a US-based analyst with the CNA Corporation, says, about a week before the "withdrawal" announcement, the Russian air effort switched to largely striking IS in and around Palmyra, yielding "a political prize and an important public victory for the Syrian regime and the Russian forces".
Syrians help a wounded youth following an air strike on the Fardous rebel held neighbourhood of the northern Syrian city of AleppoImage copyrightGetty Images
Image caption
Aleppo has already been subjected to air strikes
This, then, created the context for the partial withdrawal, and IS subsequently became the primary target for Russian air power - a point confirmed by recent US briefings.
Russia's air wing in Syria has undoubtedly been scaled back.
Indeed, analysis of satellite imagery by IHS Janes shows one of the two runways at the Humaymim air base, near Latakia, appears to have been closed.
Janes suggests damage may have been caused by over-use and this "may have contributed to Russia's decision to withdraw some fixed-wing aircraft from Syria and deploy additional helicopters".
Nonetheless, a sizeable Russian force still remains in Syria.
There is an air wing of some 20 aircraft, including about a dozen Su-24M strike aircraft and a handful of Su-30M and Su-35 fighters.
And there are still a variety of ground elements deployed to protect the air base, including highly capable surface-to-air missiles.