In the article it says that these doses were produced in a facility that wasn't approved by the FDA yet, so this has no impact on the availability of doses now. It might have an impact on the availability of doses in the future though.
Because that's how good we are as a society at efficiently allocating capital and operating supply chains. Regulators have to sign off before you can administer it to anyone but you can ramp up your production in parallel with the approval process.
Maybe the approval process includes a "must have met X criteria for the past Y months", so once you get approved, everything you've done in the past Y months counts as having been created in an approved facility. I'm just guessing though, I have no idea what the process is.
Emergent was also supposed to be approved to ramp up the full supply chain but that hasn’t happened yet, could be related.