One could make strong arguments that it should be even after the stem cell line has been created, and I would like to see that revisited.
Now, to be fair, virtually every other guideline that has explored this has said that the right extinguishes either at the creation of the blastocyst, when it's been assigned for research, or when the blastocyst is destroyed for the production of the stem cell line. So I think the position is relatively consistent within the international guidelines, but I think there are some strong arguments as to why individuals may still have a right of control over a stem cell line once it's created.
I'm afraid that right now is not perhaps the appropriate time to go into this.