Q.Should I Remove The Older Leaves On A Lenten Rose In The Spring?
The older leaves are thicker. The Lenten rose has had its spring bloom.

Certified GKH Gardening Expert
No. It will not be necessary to do this. In fact, you should disturb them as little as possible. Since you are at the top end of their growing zone tolerance, you may find that they are a little slower than they would be in a colder zone where they experience a dormancy. This rest period, actually, speeds things up.
In your zone, you will just care for it as well as you can. Likely, it won't experience much of a dormancy.
https://www.gardeningknowhow.com/ornamental/flowers/hellebore/lenten-rose-flower.htm