With the AFU units at Sviatohirsk, Ukrainian ground forces have bounced a possible Siverskyi Donets River defensive line & can rapidly move behind Russian/LPR/DPR forces at Lyman and Lysychansk.
@PhillipsPOBrien Ukraine has certainly captured Russia railway engine & rolling stock from Kupyansk south to Izyum & likely captured most between Vovchansk & Kupyansk.
The huge stocks captured at Izyum can be moved up to the Kupyansk marshalling yard & then south to supply the invasion of LPR.
@PhillipsPOBrien Railways are far superior logistical supply lines than trucks on Ukrainian roads, if they go the right way.
The rail network out of Kupyansk does just that, & the Russians left behind all the supplies Ukraine needs for this strategic offensive.
The LPR is going down in the next two weeks and the DPR shortly afterwards.
Ukraine has the LPR/DPR outnumbered, with rail supply, facing no real east-west obstacles, & LPR/DPR are lacking enough troops for an east-west defense line in any case
The Russians knew how Ukraine was going to do it to them and their collective guilty consciousnesses over their genocidal ethnic cleansing of Ukrainians did the rest.
3/6
The other possibility is this is a Kherson style demonstration to freeze Russian forces in place while AFU armored columns sweeps into the LPR/DPR territory from the north.
They are the schwerpunkt of Russia's "Special Operation."
When the LPR/DPR fall. The AFU pushing waves of displaces Russian Donbas colonists into Russia like paste out of a tube of toothpaste stomped on by Andre the Giant will freeze the Russian Army in border control/regime protection duties for several weeks.
2/4
This will be long enough to roll up all remaining Russian forces in Ukraine.
The Russian Army is simply too small to maintain control of any territory inside Ukraine's pre-2014 borders without the Russian LPR/DPR colonist forces, to include Crimea.
3/4
AFU troops are saying the RuAF abandoned all of their equipment & ammo in Izyum intact. Other reports say the same across other areas of Kharkiv. This should be enough to equip another 10k-20k AFU troops.