Dutch NOS television news reported that the problem was noted in November last year, that research was done by doctors of the Leids Medical Centre who produced their results on January 12, which were delivered to the tribunal on March 7, IIRC.
What took them so long?
Well, the drugs obviously hadn't "done their magic" so they wanted to give it a little more time. If they had only waited another week or so, no one would ever know.