The Institute for the Study of War (ISW) has reported that Ukrainian armoured vehicles are already operating beyond the last line of Russian defensive fortifications, which Ukrainian forces are currently breaking through in the west of Zaporizhzhia Oblast – although it is too early to claim that Ukraine’s Armed Forces have completely broken through this Russian defensive layer.
Source: the ISW
Quote from the ISW: "Geolocated footage posted on September 21 indicates that Ukrainian armoured vehicles advanced south of the Russian anti-tank ditches and dragon’s teeth obstacles that are part of a tri-layered defence and engaged in limited combat immediately west of Verbove (18 km southeast of Orikhiv). It is unclear if Ukrainian forces retain these positions, however."
Details: The ISW reported that they have seen for the first time that Ukrainian forces are using armoured vehicles outside Russia's three-layer defence.
The ISW emphasises that this presence of Ukrainian armoured vehicles beyond the last line of the current Russian defence layer indicates that the Ukrainians have sufficiently breached the first two lines of this layer to move their vehicles forward.
"The Ukrainian ability to bring armoured vehicles to and through the most formidable Russian defences intended to stop them and to operate these vehicles near prepared Russian defensive positions are important signs of progress in the Ukrainian counteroffensive," the ISW noted.
The ISW noted that additional geolocation footage posted on 20 and 21 September indicates that Ukrainian forces have also advanced to the west and southwest of the settlement of Verbove.
In this way, the Russian troops, currently defending in the western part of Zaporizhzhia Oblast, have failed to prevent the Ukrainian troops from advancing gradually but confidently since mid-August.
The ISW wrote that it has constantly been observing the slow but regular advance of Ukrainian troops in this area, despite the fact that the Russian military is transferring parts of relatively elite units here to strengthen its defensive operations.
Additionally, the ISW noted that Ukrainian troops conducted several drone and missile strikes on the Russian airfield near occupied Saky in Crimea and possibly damaged Russian aircraft.
In addition, satellite images confirmed that Ukrainian forces also struck the 744th Communications Centre of the Black Sea Fleet command in occupied Crimea on 20 September. Images show that Ukrainian strikes destroyed a large part of the command post near Verkhniosadove, 16 km northeast of Sevastopol.