Far future
Interesting possibility but with Earth being referred to as the lost colony, it would seem unlikely. That is assuming you mean Earth might be an original home world.
As I observed previously it is interesting to me that their technology, except for FTL, is equivalent to ours in nearly every way. This could be explained by a technical regression that occurred due to the original Cylon war.
Whatever, I like it and it has improved a lot since the first season