Russians aren't "regrouping" -- they're getting routed

The Ukrainian counteroffensive in Kharkiv Oblast is routing Russian forces and collapsing Russia’s northern Donbas axis. Russian forces are not conducting a controlled withdrawal and are hurriedly fleeing southeastern Kharkiv Oblast to escape encirclement around Izyum. Russian forces have previously weakened the northern Donbas axis by redeploying units from this area to Southern Ukraine, complicating efforts to slow the Ukrainian advance or at minimum deploy a covering force for the retreat. Ukrainian gains are not confined to the Izyum area; Ukrainian forces reportedly captured Velikiy Burluk on September 10, which would place Ukrainian forces within 15 kilometers of the international border.[1] Ukrainian forces have penetrated Russian lines to a depth of up to 70 kilometers in some places and captured over 3,000 square kilometers of territory in the past five days since September 6 – more territory than Russian forces have captured in all their operations since April.

Ukrainian forces will likely capture the city of Izyum itself in the next 48 hours if they have not already done so. The liberation of Izyum would be the most significant Ukrainian military achievement since winning the Battle of Kyiv in March. It would eliminate the Russian advance in northwest Donetsk Oblast along the E40 highway that the Russian military sought to use to outflank Ukrainian positions along the Slovyansk – Kramatorsk line. A successful encirclement of Russian forces fleeing Izyum would result in the destruction or capture of significant Russian forces and exacerbate Russian manpower and morale issues. Russian war correspondents and milbloggers have also reported facing challenges when evacuating from Izyum, indicating Ukrainian forces are at least partially closing a cauldron in some areas.[2]