I could have told you that and saved you a phone call. Std answer for them! Just like the SB A body z bar issue, never heard of it last year even though I spoke with them 5+ years ago about it.
I use a rubber mallet on the bottom side of the tube and pound the crap out of it. Helps if you can get it to rotate slightly first. Easier to do if the remaining flange is still attached to the head. Release the rear and twist it away from the head.
