Set Liveupdate to 5 hours - is it going to run every 5 hours, or does it turn it off for 5 hours?

I was wondering about the settings for Automatic Liveupdate for Norton Internet Security.  When I select Automatic Liveupdate to  "OFF", a popup window appears and asks me to "Select the Duration". 

 

I had initially thought that when I select one of the options, that the "duration" refers to the interval in which Liveupdate will run.  For example, if 5 hours is selected, Liveupdate will run every 5 hours.

 

However, now I think it actually means that Liveupdate will turn off for 5 hours, then it will resume to the default 15 minutes. 

 

What I really want is to select a duration for which it will run...NOT turn it off for a period of time, then have it default to the original 15 minute settings.