I suspect Ukraine will not regain the initiative if it fights like Russia needs it to.
If ZSU can be truly imaginative and break the offensive formatting, like @The_Capt is suggesting, then the RUS will not be able to adapt fast enough or at scale to counter it.
IF they redo the same types of heavy metal assaults then they will be fighting like Russia and Russia will inevitably, through sheer numbers, beat off the attacks.
But an assault formatted differently, that has a deep flexible, mobile FLOC and heavy back-up as needed, could work.