FWIW, NP mentioned 200 (or a couple hundred) in an interview last week. I would've preferred to see it noted in the PR to be more official, but this guidance is better than nothing. In the same interview he mentioned that enrollment would be 2-3 months as they have a lot of demand at their locations. We will see, but even if you double that and say 6 months it isn't too bad (depending on your expectations).

My projected estimates:
4-8 weeks FDA review and acceptance of P3 Pivotal Trial
3-6 months enrollment
50 week Trial (4 week overlap period + 10 week induction period + 36 week maintenance)
2-4 months for readout and sBLA filing
2-4 months for FDA approval decision
Total: ~19 months best case or end of 2020 or early 2021 or 27 months or late 2021 for the later end of the scale.

It will likely be somewhere in the middle, so mid-2021 seems reasonably and realistic without any significant delays.