I've been putting a lot more thought into the nature of the perceived time paradoxes present in this game. I think that some of these paradoxes are simple misunderstandings. Chief among these misunderstandings is the nature of time, as measured by the Mouvelian Calendar, and the reasoning behind Varra Skylark's comment at Arah: that the Elder Dragons were active roughly 10000 years ago.
Here's the substance of my brooding: Although Varra is a member of the Durmand Priory, she isn't using the Mouvelian Calendar to calculate time. I'm not exactly sure why, but I'd put it down to either i) racial bias (Varra finds norn timekeeping practices easier to understand) or ii) scholarly bias. In regards to the latter, Varra has been studying jotun timekeeping practices, so it makes sense that she would adopt them when using jotun magitech (the telescope at Arah).
So what's the difference between the Mouvelian Calendar, a human timekeeping system, and jotun timekeeping? Well, it's quite simple: the Mouvelian Calendar is calculated using Tyria's sun's relative position to the Rift. Jotun timekeeping, however, is determined using Tyria's relative position to it's sun. In other words, it takes at least 3000 Mouvelian Calendar years for Tyria's solar system to complete an orbit of the Rift. In that time, Tyria complete's an orbit of it's sun roughly 10000 times. Hence, both the Mouvelian Calendar and jotun timekeeping are correct, depending on which timekeeper (the Rift or Tyria's sun) you wish to refer to. (I believe that Lord Odran's Map of the Mists details the relationship between Tyria's solar system and the Rift.)
What this means is that when Logan and other NPCS remark that Glint has over three thousand years of memory, they are referring to the Mouvelian Calendar. What is most intriguing about this timekeeping process, however, is that Glint's own remarks support Mouvelian timekeeping practices. She see's herself as three thousand years old.
There's something in here. You all know my theory that the Elder Dragons are avatars of the Rift. I wonder if dragonkind as a whole originate from this region of the Mists? When they look into the sky, perhaps their vision, or their minds' eye, means that the dominant light source they behold isn't Tyria's sun but the Rift.