'''If I start the wrong hpf morning/evening cal set, what do I do?''' 

A cntrl-C, ''executed in the scripts window'',  can be used to stop the currently running cal script. As withh all HPF exposures, whatever is happening at the time you issue the cntrl-C will have to finish. When the script has stopped you can then issue the correct script command. 

There is a good discussion of this in a large [wiki:HetProcedures/RA/hpf#cals docement covering HPF.]