AZ-800 Study Guide: Administering Windows Server Hybrid Core Infrastructure

Hi sorry but I have question regarding AZ-800 as I have recently completed AZ-900 and I am looking for a path regarding Microsoft certification.

I see everyone talking about content of course but I am more concerned about the timeframe and how to acomplish this and still have a life outside work and studying.

Since you have to finish two exams in one year to make it even valid and then I can't find what is the expiration time.

Is this Certificate valid only for 1 year?

Because it look like they overlap as person needs to rush from exam to another exam and have only 6 month to do it and no pause for rest.

And they look to be quite massive in scope.

Then if second exam takes as well 6 months, then you have no time to prepare to renew first exam.

As for AZ-900 it has take me 2 and half months to get ready to take exam.

Or did I understand renewal process wrong?