Ukraine's ongoing Operation Vivaldi counteroffensive north of Lyman in Donetsk Oblast has driven recent territorial recoveries of over 140 square kilometers, pushing Russian forces back toward the Zherebets River and disrupting attempts to encircle the Sloviansk-Kramatorsk defensive belt. Ukrainian 3rd Army Corps units have liberated settlements in the sector, employed drone-supported maneuvers and improvised armored vehicles to neutralize infiltrations, and crossed river lines at multiple points near Terny and adjacent villages. Russian net gains across Ukraine slowed sharply in 2026, with September marking one of the weakest months for territorial advances since 2023. Trader assessments track ISW mapping for any confirmed Ukrainian re-entry into Terny amid continued frontline pressure, potential Russian redeployments from other axes, and the pace of Ukrainian consolidation before winter.