Yes, dosages were not quantified sufficiently in P2a - neither were AZ subtypes.
This is what the P2b will do based on the analysis of the P2a and extensions by Ariana and continued with the 300+ sample. Since the safety profile isn't an issue, I expect the FDA to permit further refinement of dosage and study after approval.
After all, 2-73 allows them to commute a death sentence for millions of people around the world. In the beginning, 6 months or 6 years won't matter with improved quality of life over SOC.