Is there any way I can set a "open macro" to ask the user if they would like to "update flags" run a seperate macro?

I have it set where the workbook runs a macro on open to update the flags, but if they have already opened it recently then they probably don't need to update the flags again, so I would like to give them a prompt where they can so yes or no to the update and not have to wait on the macro to run everytime.

Any suggestions...?

Thanks