Andy,
Congratulations on your long survival with MDS!
It's interesting that you were treated with daclizumab. It's been used to treat aplastic anemia, and I haven't heard about its uses for MDS. But it helped you, and that's great.
Dark urine isn't always present with PNH, but it's definitely a symptom for many PNH patients. Hemolysis may occur primarily overnight, leading to dark urine in the morning.
It's important to get that PNH test. If you have trouble arranging it, you might be able get advice from
Dr. Morag Griffin, a PNH specialist at
St. James University Teaching Hospital in Leeds.