Wagner Group captures headquarters of the Southern Military District and the building of the Ministry of Internal Affairs in Rostov, the headquarters of Russia's base of operations for War in Ukraine
I think this is a good time to continue what they've been doing, interfering with Russian logistics and pressing forward on the front lines.
They could make an attack on Russian territory (e.g. drone strikes against airbases, oilfields, bridges, or other suitable targets), but right now might be the right time to hold off on anything that might distract Russia and Wagner from fighting with each other. Nothing unifies squabbling factions quite like a serious external threat.
I wouldn't be surprised, though, if Ukraine ops to antagonize Russia as much as they can, while leaving Wagner mostly alone. That would also be a sensible strategy.