Looking on this map, I could see, that between Al Thawrah in the south of lake Assad on Euphrates river and the dam on the north of the Lake Assad, which is in the hands of Kurds, there is no bridge to cross the lake. All, what Syrian army now have to do is to reach lake Assad anywhere between those two points and cut the road, which lead to the Turkish border and they will cut ISIL down from Lake Assad down to Iraq from supplies from Turkey as well as selling oil to Turkey. Cutting their supplies from Turkey, ISIL will be quickly overstretched in many fronts in Syria and in Iraq and would be quite quickly destroyed.
I think no matter what happens this is going to be a really tough battle, ISIS know the consequences if the SAA take Al Thawrah so will no doubt be reinforcing this to the hilt, and then you have the problem of defending it, bearing in mind ISIS could attack from the west/north/east, as well as trying to flank it coming from the Resafa direction. I think that Resafa needs to be taken before taking Al Thawrah. And i think that the Tiger forces will target Deir Hafir next which in effect will cut ISIS into segments, and hoping for the same kinda of scenario as the east Aleppo cauldron, between Jirah airbase and Tabqa airbase, ISIS will have only two options die or swim Lake Assad lol
once the Kurds attack Manbij which will hopefully take some reinforcements away from Al Bab, then the SAA can take Al Bab. Palmyra and Qaryatayn once taken will fragment ISIS even more blocking supply routes from the Al-Tanf–Al-Walid Crossing.