Do different junctures cause a feng shui site to be considered different sites?
My heroes just attuned to a feng shui site in the Past Juncture.
The same site in the Contemporary Juncture could be owned by a different faction. If they liberate the Contemporary version, are they considered attuned to 2 separate sites?
The assumption here is that the spot is still a potent Feng Shui site in different junctures. It's very possible that most sites in one juncture don't line up the same way in later or earlier junctures. The landscape may have changed too much and the chi runs differently, especially for the generally minor sites that players are likely to gain control of. In other words, this doesn't have to be an issue if you don't want it to be.
That said, if controlling the same site in two junctures is a fun idea you would like to run with: I say it works.
Each juncture is essentially it's own place, and the players would have to work to claim "the same" site in the new juncture, so you might as well reward them for the effort.
From an in-story time travel perspective: If the player are connected to a site in the Past, but aren't linked to it in the Contemporary, then linking to it would be a source of more power. Shui sites are concentrations of the local chi flow. If you view chi flow like a river, taking a bucket of water out of the river in January, and taking a bucket of it out in June, you get two buckets of water, and with time travel, you could have them both at the same time. The rivers, however, will be different in nature in those two seasons, and similarly the nature of a shui site in two junctures will be different. It's power may have waxed or waned, or become tainted or changed by the surrounding world.
I would say they are the same site but because they are in different time periods, they only count for the particular time period they are in.
So although they are the same site physically, they don't count as controlling two sites .... although they may count as such in the Netherworld.
They are the same site and you really have to link to two different sites to get the benefit.
Now you could say because they are in different time periods they are different sits so this is OK.
In this case it should be very difficult to protect the same site separated by time