Sorry. Not supported. Reversal is not possible using that note when using HU's. As a result, once the material is posted to UR via the usage decision it is done. There is no going back.
You have to write off the material and create a new PO.
There is no additional SAP note to the best of my knowledge. I would suggest you contact SAP and at elast make them aware of the desire for this ability. The more people that complain, the more likely SAP will do something someday.
Craig