A breakthrough in this area puts serious stress on Russian positions in Izyum and Lyman as Kupiansk is a key supply node."
The spear is pointed directly at Kup’yars’k - come within 10k and its effectively over for the entire Russian supply chain in Ukraine.
More than stress, rather put paid to all Russian forces in Ukraine. The entire rail line which Orcs depend on for supplies will be cut.
The only other way for the Orcs to resupply is by truck from Starobil’sk (south of Lyman) which is too far from Russia for any realistic timely supplies.