Whatever happened to the dragons?

Postage in the city of lavalin has been sitting alone, seeing the wear and tear of age and time. And in big bold letters we're in a slight red and gold reads, "Where have they gone?".  Followed by a few sentences by the author weathered down to being illegible. But the name of the author, and a bright red wax stamp still holds the postage strong.  The stamp represents the library, specifically the head of History who has kept a number of artifacts and historical ledgers throughout the passing centuries. 
It has been common knowledge that dragons have been long gone Way beyond the veil appearing. And many believe that this is connected in some way. But as there is no dragons to clarify it is all been circumstantial evidence. The last known dragon to appear within Sirva was a gold dragon speaking ominously of a transition. The Gold dragon disappeared, so did every dragon that is known to the world. Uniquely though, dragonkin still do roam the earth. Such as kobolds, wyverns, and basilisks still can be seen even today.  Even though Cobalt are known for worshiping dragons even they have gone astray not knowing where their masters are.
And so we come back to the postage, where did all the dragons go?

Why is the sleeping dragon alone? Why is the dragon's horde seem to be protected? Why does the dragon sleep so soundly. And why when I look at it do I hear a whisper, a whisper at going through my mind telling me that the dragons cannot wake yet. That there will come in time but if that time comes too soon disaster will strike us all. God's help us we know not will come when they awake.