Re: Helmet certification for 2021
...the wording of "SA2010 helmets are legal throughout the 2020 season" is telling you that they are good for 2020, no longer.
It's a bit more nuanced than that (which may be a Lemons first). HQ is waiting to ban SA2010 helmets until the SA2020 helmets are readily available, for some definition of "readily available." Nick has suggested that one practical consideration will be the point at which they can be reliably supplied via the Lemons storefront. On the off chance that this doesn't happen right away, it may very well turn out that SA2010 helmets will still be okay for the first race or so of 2021. Essentially they don't want anyone to feel forced into getting a "temporary" SA2015 just because they can't yet easily take possession of a SA2020.
I haven't been following the supply question closely, so I don't know where any of this stands as of right now.
1980 KV Mini 1: Worst of Show and Fright Pig Supremo 2009 Concours d'Lemons
1978 H Special: Second-Round Elimination 2010 Lemons Pinewood Derby at Sears Pointless
1967 SAAB 96: IOE 2012 Pacific Northworst GP, Organizer's Choice 2022 Hell on Wheels California Rally