Pokrovsk and Kupyansk are cooked at this point. Eyes are now on Lyman, Siversk, Kostyantinivka with Russians already establishing a foothold in those key towns. It's actually getting more and more difficult for Ukraine to pour in numbers to any one as Russia seems to be moving on several fronts, even Vovchansk in the north is on the verge of falling.
I guess the questions now are
1) how long will it take for Russia to fully capture Donetsk as they start threatening Kramatorsk and Sloviansk
and
2) what will Russia do once it has Donetsk
this has been the obvious point at which they'd agree a permanent ceasefire / peace deal on status quo lines, without needing to haggle over land swaps. But they'd still care about nato expansion and the militarization of west Ukraine
we could be talking a year out