I’ve found pandoran nest with operating range 0. Some lazy pandorans. What are they doing there?
The ranges grow over time, when they span than always with 0 range.
Interesting. So how can I see this nest? They can’t attack with 0 range surely?
I guess you researched the Citadel recently, this one reveals pandoran structures in your scanning range 
So I’ll see all nests before they change into lairs and citadels? How would they evolve then? It’s not game over for pandorans if you see all nest before they turn into scyllas?
Well, Lairs and Citadels can also spawn from scratch. A little flaw of the ‘growing story’ they told us, but I guess (currently) necessary to make it not too easy for the player.
Edit:
Also they grow sometimes pretty fast, I think it is dependant on how much are left, so how you react on them.
And finally they can also spawn in areas outside the scanning range and then have time to grow unspotted.