I don't think a timeline has been set yet but it will be more than 5 years! It will probably be of a similar length to vanilla. The impression I and others get with with Westeros is that it is a static society that has really developed over 1000s of years, so probably wont develop much over the coming few centuries. So the general consensus on the board (http://citadel.prophpbb.com/) is that technological/economical development wont be a big factor of the mod. Someone even suggested replacing the technology mechanics with something else entirely, with things like preparation for winter.