5,000 square kilometers in four months
December 2016 was a good month for the Syrian army. It finally expelled rebel forces from eastern Aleppo thus taking full control of Syria's most populous city. But it was not without drawbacks.
So many of best Syrian units were in Aleppo that defense of Palmyra was left to easily-spooked second string formations. ISIS took advantage of that, launched a shock offensive of its own and quickly took the town, as well as chased the defenders a further 60 kilometers -- all the way back to the T4 airbase.
At this point the Syrian government controlled less of central Syria than at any time since the start of Russian military intervention in September 2015. On a map it looked like this:
After successive Russian-backed offensives the map now instead looks like this:
Syrian government forces have gone from having almost no presence in central Syria to taking some 5,000 square kilometers in just four months since the offensive to retake Palmyra was launched in early February.
The Syrian army is now just 30 kilometers from Suknah. The effort to reach and take Suknah is expected to be slow because the terrain is difficult and easy to defend for ISIS (the road to Suknah is dominated by highlands to its north). However after Suknah it is all open and flat desert all the way to Deir ez-Zor.
As an extra bonus for Damascus its gains against ISIS means the rebel pocket of eastern Qualamun is now wholly encircled by loyalist forces, and as it is not envisioned as one of the four de-escalation zones and where it previously dreamed of linking up with US-trained rebels in the south will now have to start thinking about folding.
On most days in the war in Syria only very little territory changes hands thus perhaps giving the impression that front lines are static and almost never change. That is not true. In a timeframe of months rather than days changes in who holds what can be very dramatic.
So far in 2017 no part of Syria has seen a more dramatic change in favor of the Syrian government than central Syria which is incidentally where Russians and the Russian-trained "5th Assault Corps" have been the most active.