RoboHelp 8 RHCL .exe command-line, can this automate updating of linked .fm files?

My work flow is as follows.

.fm files -> .book file -> linked in RoboHelp 8 project -> automated build of WebHelpPro via RHCL.exe.

If any of the .fm files are changed, the changes are NOT propogated to the WebHelp I generate because running the generate command from RHCL does not update the linked .fm files.

If I follow the same work flow but build WebHelp from the RoboHelp GUI then it prompts me, "Do you want to update linked files?"

So my question is, "Is there any way to force updating linked files at generate time?"
RoboHelp project property?
RHCL command line argument?

Thanks in advance,

Matt Moore