Thank you for the very clarifying reference. Even if I used Voice a fitting example I had not thought of looking at the range in particular - and so it goes that it solves the question. I reckon then that this holds true as well for the other ranges - namely Touch, Sight and Eye (Personal and Arc being of little consequence here).
In the light of your work and great examples I would agree that this seems to be something the author(s) didnt think about - at least there seems to be no explicit text on ongoing Intellego effects and Range. I have voiced this out of interest - and not because it is currently actual in my own saga. If I was met with a similar situation with my troupe I would probably allow the continued input of information of an Intellego spell even if out of range, at least when keeping with relatively simple things like whether a door is ever opened - as in the thread inspiring this consideration. But I might also rule that if there were specific details or changes in the spell, the range would have to be reestablished.
Anyone out there with an argument against this or the opinion that this should be interpreted differently?