What kind of fight is happening when Zelensky is waiting for equipment from other countries and training is happening when the war is already on?
Set aside Political issue here, this sentence is trouble if I am a Russian Commander in charge of the field
You know the west are sending somewhere upward to 300 Tanks/IFV/APC to Ukraine, unless the West also sending crew to crew those vehicles with, Ukraine is going to need to send soldier to train to use them, and you don't send newbie noob and look for a long course to build up their base, you send your best, your regular, so they can quickly master those equipment and put into good use.
300 Tank/IFV is more or less a Armour Division worth of stuff, and then you also need to match the Armour Division with an Infantry Division (theoretically, you will need two, one to accompany the Armour Division and another to secure the objective once they were taken by the Armour Division), which mean Ukraine has at least pulled 2 experienced division, may be 3 off the line, and that is a big chunk of proper combat power, that's 20,000-30,000 men, they weren't in the frontline, they were in Germany, Poland and the UK learning how to use Leopard 2, Bradley IFV, Marauder and training on how combine arms doctrine.
Russia on paper should have been making a big (well, bigger) progress because of this rotation, the thing is, beside Bakhmut, that current Russian push is not making headway anywhere else, and Bakhmut is a small corner of the battlefield. And the window for Russian to push is closing soon when the snow turn to mud in Eastern Ukrainian Spring. And you know once it hit summer and the ground harden because of the heat, you are looking at the influx of that 3 division, or 9 Brigade, or 30,000 men in a counter offensive, you will need space/strategic depth to blunt the Ukrainian counter offensive. And if they can't break out from Bakhmut, you are looking at a reverse gain from the Ukrainian side. Unless Russia suddenly gain the momentum in the remaining 18 days of this month, because traditionally Ukraine see a lot of rain in April