Referenced by Stig earlier, this link may offer some speculation as to the air units most likely employed in the attack on Blankenburg. I'm betting on the 366th Fighter Group.
https://www.armyupress.army.mil/Port...x-tac-team.pdf
"On 17 April, two fighter groups of XXIX TAC flew escort for a massive three-and-a-half hour raid on Magdeburg by 11 groups of medium bombers dropping 775 tons of bombs that ripped the heart out of the city.100 The ground forces felt the impressive display, a f itting bookend to similar operations at Brest seven months earlier, did little to assist in the reduction, as most of the bombs fell on the city’s center while the defenders had dug in on the perimeter.101 Nugent sent Simpson a photograph of the ruins, along with a note, which read, “The ruins shown on attached photograph were formerly the city of Magdeburg-until it failed to accept the ultimatum of the Ninth US Army.”102 But the 30th Infantry Division and elements of 2nd Armored quickly reduced the stubborn holdouts the following day. Further operations on German units east of the Elbe risked attacking Soviet formations, and the Allies agreed to a 200-mile bomb line in front of their forward units, which eventually placed an umbrella over the German forces remaining between the two armies, curtailing operations for XXIX TAC and allowing many of the surviving German forces to reach British and American lines on the Elbe. Only the light-artillery spotting aircraft could operate within this restricted airspace, and it was one of these aircraft that f inally spotted the approaching Soviet columns.103 On 25 April, First Army’s 69th Infantry Division earned the honor of making first contact at Torgau, a distinction that surely would have gone to Ninth Army absent the stop order. Behind the Elbe, XIII corps elements had to deal with a counterattack from Panzer Division von Clausewitz, a school formation fleeing the British sector for either the safety of the Harz Mountains or other enclaves farther south. But hasty redeployments by the 29th Infantry and 5th Armored divisions resulted in the German formation seeking shelter in a densely wooded area, where the attackers destroyed it.104 The 366th Fighter Group provided key support on 19 April, with Major General Gillem reporting, “The close cooperation given in this afternoon’s attack by squadrons of your group to the armor of my Corps established a new high in air-ground cooperation. Your bombing was so accurate the ground troops were able to close effectively with the Krauts.”105 The going was tougher in the Harz Mountains, where the 83rd Infantry Division requested close air support against “‘Mount Olympus,’ a rugged mountain-top stronghold where the enemy resisted bitterly,” but attacks by 41 dive bombers helped reduce the position.106 With most of Ninth Army now in position on the Elbe, the headquarters moved forward again on 23 April to Brunswick, in the center of the assigned occupation zone, to await the arrival of the Soviets from the east.107"