Council of Elrond

I read this in the Rulings Digest #117 and I'm confused:

However, those site cards are placed with the agent/hazard host, meaning that the site cards are reserved for that purpose only. They may not be used for other purposes (i.e. company movement, playing cards on the site), unless so specified in the rules or card texts. Global-effects (i.e. Long Winter) still affect these sites as well.

When are the effects of Long Winter applied? Immediately when the card comes into play? Are all the sites in play (the sites from companies that have already moved, the sites of origin and destination from companies that are moving, the sites put "off to the side" by the effects of cards such To Get You Away) tapped immediately at once? They also tapped the sites from revealed agents? An the sites from the hazard player, also tapped immediately?

Environment. Each moving company that has at least two Wildernesses in its site path must return to its site of origin unless it contains a ranger. Additionally, if Doors of Night is in play, each non-Darkhaven site in play with at least two Wildernesses in its site path is tapped. Cannot be duplicated.

The tapping of sites is an action created by the passive condition of two wildernesses in a site's site path and Doors of Night in play.

CRF Passive Conditions wrote:If a card specifies that an action is to occur as a result of some specific passive condition, this action becomes automatically the first action declared in the chain of effects to immediately follow the chain of effects producing the passive condition.

If more than one action is required to be the first action declared in a chain of effects, the player whose turn it is chooses the order in which they are declared. No other actions may be declared in this follow-up chain until the multiple required actions have been declared.

When all the conditions are first resolved, an action is declared for each applicable site in whatever order the resource player decides. This chain of effects occurs immediately following the chain of effects which produced the required conditions.

After that, if at any point a site is revealed that matches the conditions, an action will be declared to tap the site as a new chain of effects immediately following whatever chain of effects revealed the new site.

As a side note, it really doesn't matter if site cards are tapped while an agent is using them, as the site cards are returned to the location deck no matter what.

Thanks!

Also keep the CRF for Long Winter in mind:

Will tap all sites in play that meet the requirements.
Long Winter will not continually keeps sites tapped, it is only applied once to each site each turn.

So you could untap a site the same turn the tapping effect of Long Winter applied without it being tapped again.