If you compile your program between debugging sessions, you should remove your program from CA Intertest control which will delete your existing breakpoints. You then must issue a CEMT SET PROG(PROGRAM NAME) NEW to refresh the load module. Then put your program under CA Intertest control again and set breakpoints.
The Symbolic listing is used to navigate the load module. So best practice is to make sure the load and symbolics match. CA Intertest for CICS will issue a warning message to the user when they try to set a breakpoint if the load and symbolics are not in sync. The warning message is only issued when the first breakpoint is set. The user will be displayed the following message
CAIN8002 WARNING - Symbolic file date/time not equal to load module date/time.
The user can override the warning message which is not recommended since you can have unpredictable results when testing. A mismatch listing may be used if the programmer does not have the ability to create a matching load and symbolic and they are trying to debug a production problem.