I think they got the brunt of it Neil.
This is something I put together about 10 years ago from various sources - I can't remember which. Some stuff you may recognize but I make no claim to being the author. This is the part about Y-29.
JG 11 went after the 2nd TAF airfield at Asch in Belgium, operational base for four Spitfire-squadrons. The attack on the Asch airbase, known as Y-29, was a total disaster. When JG 11 reached Y-29 they found eight Thunderbolts of the 390th Fighter Squad, 366 Fighter Group circling the field and twelve Mustangs of the 487th Fighter Squad, 352nd Fighter Group just taking off.
The Luftwaffe units assigned to attack Asch in Belgium were the I, II, and III Gruppen of JG 11, commanded by Oberstleutnant Gunther Specht, Kommodore of the Geschwader. The three Gruppen of JG 11 were stationed at Darmstadt-Griesheim, Gross-Ostheim and Zellhausen all southwest of Frankfort. Sixty-five Fw 190's and Bf 109's of the three Gruppen of JG 11 took off from their respective bases just before 08:30 hours and formed up over Aschaffenburg, joining with two Ju 188 pathfinders and headed for Asch. Radio silence and low altitude were the order of the day. So secret was Unternehmen Bodenplatte that the Germans own ground forces were not notified of the large formations of German fighters that would be flying overhead. This resulted in at least one casualty for JG 11 as they were assaulted by friendly fire on their way to Asch.
On December 31st 1945, the 352nd had received its orders for the 1st day of the New Year. They were to provide escort for 8th Air Force Bombers on a mission to bomb targets near Berlin. The 366th also had received their orders for the New Year. The 391st was to leave early in the morning to attack German armor at Ondenval. Two flights of the 390th were also scheduled to take off slightly later in the morning with the same objective. Thus it was that eight P 47's of the 366th would be circling over Asch, and twelve P 51's of the 487th would be on the flight line as the Luftwaffe approached.
As JG 11 approached Asch, the eight P 47's of the 390th were just forming up over Asch to head out over the Ardennes in search of German armor. As the 390th finished forming up they spotted flak bursts over the Ophoven field. At this same moment Lt Col. John Meyer was just beginning to roll down the runway. Heading for Ophoven to investigate, the 390th was surprised to see a large formation of Fw 190's and Bf 109's approaching Asch from the northeast at 1500 ft. The eight P 47's of the 390th jettisoned their bombs and external tanks and attacked, breaking up the formation. This turned out to be a key blow to the JG 11, without which the mustangs of the 487th may not have so easily taken to the air. The 390th claimed seven German aircraft in this attack taking a loss of only one.
Meanwhile Meyer was lifting off with the rest of the 487th behind him. As he rose from the runway he found himself faced with the oncoming JG 11. With a full load of fuel in his fuselage tank, making low altitude maneuvering difficult, and gear still retracting he fired at an oncoming Fw 190 scoring hits and sending the German aircraft crashing into the field. Meyer went on to claim a second Fw 190 before the battle was over.
The battle over Asch went on for 30 minutes. Eleven pilots of the 487th claimed twenty-three victories while sustaining no losses, and just three aircraft damaged in the air. Among those killed or missing from JG 11 were Lt. Alwin Doppler of 2./JG 11, Ofw. Franz Meindl of 8./JG 11, Major Günther Specht of Stab./JG 11 and Alfred Mannchen. JG 11 also lost Hptm. Horst-Günther von Fassong of Stab./JG 11 with 136 victories (including four four-engined bombers) when he was shot down and killed near Maastricht. Ofw. Karl Hiller of Stab III./JG 11 was shot down and taken prisoner. On the return trip several more JG 11 and other German fighters fell to friendly fire before the German guns could be called off.