I'm sorry my suggestion and message were unhelpful to you. I missed the postponement part. I agree that 3 weeks is way too much time. It's often the case that breast cancer patients have to "shout" to be heard. Call them back, and tell them the additional wait is unacceptable if not downright cruel. Demand that the earlier appointment be honored. The last thing you need on your plate is to be jerked around by your doctor. I've done a lot of research, and oncologists who become breast cancer patients are often stunned by the patient experience. They don't get us. It's like a parallel alternate universe.

Unless it's a delay on the lab's part. Then complain about that.