G’Day,
I recently renewed one of my Azure Certifications, extending it by another year from the original expiry data.
You can extend any certification that is about to expire within the next 6 (six) months. You can’t extend them if the expiry date is any longer than 6 months in the future.
The process was quite straight forward and I was surprised at the easy with which I was able to walk through the whole process (not the actual questions, those required a bit of thought 
) – especially as I had previously took many online exams at home and had to verify the integrity of the temporary exam room that I had set up.
The only difficulty that I had with the process was actually starting it.
I remember that I got an email a few weeks ago stating that I needed to upgrade within 6 months, well I now could not find that email and I wanted to get the upgrade done.
After a bit of research, I found that I needed to associate my certification profile with a Microsoft docs profile.
After that I found that there was a link from my docs home page to all the certifications that I needed to update.
After linking my account I found that the certifications that you need to update will be listed under “Certifications” on your docs page
Just hit “Certifications” in the left had menu and then any exams that need renewing will appear in the middle pane with a “Renew” button next to them.
Then you are straight into the exam, a series of untimed questions that will cover some of the latest enhancements and just ensure your knowledge is still current.
Good luck.
Have a great day.
Cheers
Martin.