Yes, I've filed a bug for that. Given the fact that Android technically
does not follow guidelines (and 2021a1 possibility), I will try to fix that
in Android 13. 
But we won't be able to deliver that change for already released devices.

Thanks,
Almaz

On Fri, 24 Sept 2021 at 17:23, Paul Eggert <eggert@cs.ucla.edu> wrote:
On 9/23/21 6:59 AM, Almaz Mingaleev wrote:
> For Android having 2021a1 and 2021b would be inconvenient. Because
> there are hardcoded places which expect that tzdata version is exactly
> 5 characters. And we can't update that code along with time zone files.

OK, but can you please fix this in Android? That is, please put in a bug
report or whatever it takes to start the machinery to fix things.

You don't need to fix Android right this second, but please don't put it
off until the year 9999 either, as the sorts of changes that we have
been discussing post-2021b are very likely to generate version numbers
longer than 5 characters in the not-as-distant-as-the-year-9999 future.
Plus, the guidelines already say that release IDs can be more than 5
characters.

Thanks.