I wonder Russia did not use so many long range guided MLRS in the initial assault.
This reminds me, one very important question is how effective the sensor-fuzed submunitions for MLRS were in this conflict. I bet all the world's militaries are rushing to find this data. This was a key sticking point for the US after Iraq too. Because the USAF may have used their clusters ineffectively (targeting armor which was not in the open.) The critics of this technology argued that these submunitions weren't effective. But it could've just been improper use. This conflict just provided another battle test of this technology.
By the way, there were heavy MLRS barrages in the opening phase, but (at least according to the very unreliable twitter footage) did seem to drop off in frequency. I'm assuming (for now) the Ukrainian formations would have dispersed after the first day because of the devastating effect of those opening salvos. But we really need data on the first question (of effectiveness) to know what happened.