OK, it seems I haven't been as clear as I have meant to be regarding the Agents of the Gods campaign. Probably too many late nights and not saying all the things I meant to.
There are a couple of issues that I want to kind of clarify.
Time:
Time is an interesting thing in general, and especially for the Agents. Celestial Beings do not age the same way Mortals do. For the most part, non-native outsiders don't age the same way Mortals do. As a result, they perceive time with a different level of importance. Most outsiders perceive events, not the passage of time. They are aware that time is passing, of course, but it is less significant how much time has passed. This is, in part, due to their 'lifespan', but it is also due to relative time.
The material plane is the cosmological constant for time. (OK, that might not be 100% accurate, but it is for all intents and purposes of any of the campaigns right now.) The more detached and distant your location is from the material plane, the slower time moves in relation to the material plane. The immediate, transitionary, planes usually move at about half the speed of the material. The planes beyond that tend to move at about half the speed of the transitionary planes. Planes that branch off beyond that move even slower. It is often the case of halving each time. That is not a constant though. It is just likely to be the case. Some mortals have sought to cheat death by creating a chain of demiplanes and then sequestering themselves into the furthest plane down the chain. It seems like a good idea, but since these are demi-planes, the results are hardly ever what is expected.
Additionally, you have a couple of planes the don't behave correctly in this manner. The Spirit Realm overlays the material plane so closely that time passes exactly at the same rate. The Shadow Realm is much more fluid and time often moves faster through it. This is how many transportation magics work, by accessing the Shadow Realm. The Faerie Realm is very chaotic and it is impossible to predict how time is passing within it at any given time. Perhaps Powers and Gods can figure it out, but others have not.
I am going to include a
very rough diagram of how the planes sit. It isn't 100% accurate, but it does provide a general foundation for you to figure out from.
The Material plane is the circle in the center. You can see that the Spirit, Shadow and Faerie Realms are closely associated with the Material. You might also notice a couple of demiplanes overlaying the Shadow. Again, this is the realm of preference for building your own planes from. Most planar travellers are passingly familiar with Shadow and it's malleability makes it easy to build off of. The Spirit Realm has two primary methods of travel. Mortals die to get in. Outsiders use gates built by Gods to get in and out. It is otherwise impossible to enter the Spirit Realm. (There are allegedly Mortals that can pass their Spirit from their body into the Spirit Realm, but it is not an easy process and it has some danger associated with it.)
You will also notice the Wilds of Avondell as one of the transitionary bridgepoints to the Heavans. The other listed transitionary plane is the Crags of Minar, which is closely associated with the Hells. Please note one of the many inaccuracies here. The Crags of Minar and the Wilds of Avondell also overlay each other! One or two Hellish Realms also overlay the Wilds of Avondell. I built the diagram more as a representation for time, not interconnectedness!
The Wilds of Avondell move at half the speed of the material. Lune's, Belmay's and Pter's Realms overlay the Wilds and each of those moves at half the speed of the Wilds. That means it moves at 1/4 the speed of the material. For every day that passes within Lunes Realm, 4 days pass on the material. Please note that I have place a smaller plane on each of these as well. So Lune's Glade might move at 1/8th the pace of the material realm. Of course, I have said that these are inaccurate. Some of the Gods keep even more secluded realms that might move at a completely different pace.
The demiplanes that are adrift move at wildly different time. Once they are linked, somehow, to the Material plane, they begin to sync up with it. This is what is slowly happening with the little plane the Agents reside on. Right now it is moving much slower. Enough that 50 years on the material plane are significantly less on your plane. But it is slowly speeding up to match. In terms of material time, it will still take centuries before it might be down to a 2-1 ratio.
What is the current 'exchange rate'? You don't really know until you leave. And since you tend not to measure time in a significant way when nothing interesting is happening, it's hard to tell.
The point is, I will be referring to material time within the game.