Changing default TTL for keys

Hello!
I know that the TTL can be changed during authorization:

Can I change TTL for keys (default 12 hours) on the server side?

If you’re using Teleport Enterprise, you can edit the max_session_ttl parameter of the role that a Teleport user is granted when they log in:

spec:
  options:
    max_session_ttl: 1h

With Teleport OSS, you’d need to edit the admin role but I don’t believe this is acutally possible. You can try tctl get role/admin > admin.yaml on the Teleport auth server, edit the value in admin.yaml and then tctl create -f admin.yaml but I suspect it will fail as role support isn’t part of Teleport OSS.