What is your source? Not being argumentative, just trying to figure out who knows what.
Here’s the press releases from when they finished gathering the data needed from the Phase 3 clinical trials:
Pfizer - https://www.pfizer.com/news/press-release/press-release-detail/pfizer-and-biontech-conclude-phase-3-study-covid-19-vaccine
Moderna - https://investors.modernatx.com/news-releases/news-release-details/moderna-announces-primary-efficacy-analysis-phase-3-cove-study
You can find the actual study data here:
Pfizer - https://www.fda.gov/media/144245/download
Moderna - https://www.fda.gov/media/144434/download
So they had everything they needed then. Filing for the BLA requires additional monitoring of study subjects primarily for safety. There was always a plan to break placebo, but the timing was always fluid based on conditions and based on what the FDA and CDC had to say.
There’s some excellent discussion on this in this article from November https://www.statnews.com/2020/11/12/pfizer-says-placebo-patients-will-eventually-get-its-covid-19-vaccine-the-question-of-when-is-complicated/ and in this December article published in the Journal of the American Medical Association: https://jamanetwork.com/journals/jama/fullarticle/2774382