My guess is the US has stepped up passing Intel to the Ukrainian attack units, probably down to the position of individual soldiers. That allows the Ukrainians to identify weak places in the lines to attack.
That means the US is facilitating suicide bombing.
The Ukrainians don't need the US to gather that data. They have real time drone images which let them count how many Russians are in a particular foxhole, and they have a steady stream of observations, images, and videos provided by friendly locals.