Just like the cub stages, but on the other side of life.
I think it could be neat to add one or two older stages:

"Mature" from 10 -12 years: lion(ess) is slightly leaner/less muscular and they hold their head higher.

"Elder" from 12 on: lion(ess) is much leaner/frail and they put their heads in rested positions.

This would be an GB service available in the Oasis just like the counterpart.

Also, if you don't support, why not since it doesn't affect your Lions? Any I'm happy to adjust the semantics/details, please give me your feedback.