If you execute any programs that have been CA Optimized you must have the CA Optimizer runtime started on the LPAR. If the runtime is not active the program will abend when it is executed.
To remove CA Optimizer the client would have to recompile all their programs without CA Optimizer using the standard IBM compiler.
In the Users Guide they have a report called the MRS report that you execute pointing to a load library. This report will identify which programs are CA Optimized and need to be recompiled.
A RUNTIME-only license is available to reduce cost. The runtime-only license will provide support for CA Optimized programs. But this license will not allow programs to be CA Optimized.