In essence, as Americans were busy bombing small Syrian groups entering their declared exclusion zone via the main road, a separate Syrian force staged a lightning-quick advance through roadless desert, well to the east of the "deconfliction" zone enveloping the Americans.
If the US forces are not cut off from ISIS they no longer have an excuse to continue occupying this part of Syria. (Or will they insist they get to leapfrog over the Syrian army?)
Russian officers also accused the US of hindering the Syrian war effort against ISIS, by blocking its military from opening a new front against the group:
The new, and improved, map with the Americans and dependent forces (green) now boxed-in by the Syrian army (red)
UPDATE -- Apparently in sync with the Syrian army move south, Iraqi forces likewise advanced against ISIS from their side and met on the border. Thus Syria has not just reached the formal Iraqi border, but actually re-established an actual link to Iraq:
The Syrian government forces have reached the border with Iraq after fighting against Daesh terrorists near al-Tanf in the country's south after Damascus' allies had been bombed by the US-led coalition for the third time in the area, the Syrian Army's command announced.
The news comes after on June 8, the US-led coalition bombed pro-Damascus forces near al-Tanf in the area of a deconfliction zone following an alleged attack by a combat drone resulting in no coalition forces' casualties. This was the third attack by the coalition on Damascus' allies in the area. The coalition targeted a drone and trucks with weapons.
"Units of our [Syrian] armed forces with the support of allied forces… were able to reach the border with brotherly Iraq northeast of al-Tanf and establish control over a large number of strategic positions in the Syrian steppe," SANA news agency reported citing the Syrian army.
The Syrian military noted that the fact that it has reached the Iraqi-Syrian border is "a strategic turn in the war on terrorism and a base for expanding military operations in the steppe and along the border with Iraq."
According to the command, the success in this region "tightens the stranglehold over what remains of Daesh formations" and cuts their supply routes in several directions.
On Friday, the Russian Defense Ministry slammed the move, saying that it seems that the US-led coalition is more interested in bombing the Syrian army instead of fighting terrorists. It also accused the coalition and Syrian rebels it supports of "conspiring" with Daesh leaders by letting them leave encirlement and move to other areas.
Veteran Green Beret and Special Ops Soldiers Admit U.S. Trains Our Enemies in Syria
Syrian fighters under the guidance of U.S. forces are also working for ISIS and other combatant groups, and how this detail is being willfully overlooked or covered-up.
While the press has reported extensively on the over 100 armed groups within Syria vying for control, and the occasional report comes out about U.S. special operations troops in Syria and wasteful spending on covert action programs, the wider story about the U.S. Special Forces arming Syrian anti-ISIS forces while the CIA conducts a parallel program to arm anti-Assad regime forces has yet to be told—until now. It is a story of fraud, waste, and abuse, as well as bureaucratic infighting and a disgusting excess, which has only contributed to perpetuating the Syrian conflict.” [Source]