Their total advance was 50km over 3 days.
Thats from Zelensky’s statement, and he low-balled it. At the time he said it some Ukrainian units were already on the Oskol, another @15-20 miles on.
Rommels 7th Panzer managed about 160 miles from May 12-May 24 1940 (Hitlers halt order). Or near Dinant to east of Boulogne. That gives me about 13 miles/day.