If understand you correctly, the answer is no. EPG Update only reads any existing xmltv file and updates GBPVR's EPG. It does not update the xmltv file itself. Since there are so many different ways of getting the xmltv file, gbpvr does not know which way you use, so you will have to do that some (any) other way.
One way that works really well is to use the updateEPG.bat (create it if it doesn't exist), which will run every time before the EPG is updated. In there you can put
XMLTV.EXE TV_GRAB_NA_DD --OUTPUT tvguide.xml
if that is what works for you.
I'm not always right
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