Not quite. If you pass the hiring committee, you have one year to find a team. So it's more like your interview result is good for a year. After you match with a team you get the actual offer and it has the usual deadlines.
Hiring processed has changed though, so I'm not sure if this is still true.
team matching has been removed. Now you get interviewed for a specific role, which streamlines the process quite a bit and saves time for everyone.
I have not found 4 days to be a usual deadline at any other company.
think they tell you its exploding. but if you end up turning them down they reach out a few months later and tell you its valid for a year