Winter is arriving. Both sides will effectively shut down until April/May. The Ukrainians will consolidate their gains and replenish their weapons stocks. The Russians will do the same.
Hopefully, peace negotiations will get this stopped.
The last major metropolis that the German Army captured in World War II was the recapture of Kharkov. The Russians had taken it in cold weather fighting and the Germans retook again in cold weather. There will be some winter festivities in this war too.
Not much to negotiate. The Russians need to get out of Ukraine.