I'm not really sure how to answer that.
If your using a mix that contains no N at all then I'd be wanting to add just a little.
Do prescription nutes have a recommend dose for this late in a grow? If so then I'd be thinking of adding perhaps a third of what they suggest, but incrementally, so as not to shock the plant.
As
@Krissi Carbone rightly says, every plant is different but, GT is generally very sensitive to rapid changes in ec and too much nitrogen generally will prevent it from properly ripening.
Indoors for proper ripening you may want to reduce the day light also. The more extreme Thai phenos seem to take forever, even outdoors.