Hi,
I am an admin of our trello team, in fact I created it. We have a lot of old boards which we are trying to archive, but many of them were created by others.
My understanding, was that as an Admin, I should have the option to change my permissions on the board to become a Board Admin. However, when I click on my avatar, the option to do so is greyed out:

So I'm a bit stuck and I don't want to have to go around the team and ask them to close the boards they've created, if they are still here....
Any information would be appreciated.