What happens to an investigator who arrives at a gate already explored by another?

Question

Say Investigator A goes through a gate and comes back to Arkham, and Investigator B moves to that location. What happens, assuming A goes before B?

Here are some cases:

If A moves to Arkham on his movement phase, then B moves to the gate location, B can hand A an elder sign to then use to seal the gate, correct?

If A moves to Arkham on his movement phase, then sits at that location and, in a later turn, B comes to the gate to give him an elder sign but is first to act in that turn, then before A gets a chance to seal the gate, B gets drawn into the other world, correct?

It seems pretty straight-forward as long as we observe the phase to phase step-wise turns, but I wanted to be sure that such a plan, to pass items to help someone who wanted to seal a gate, would work and that care needed to be taken how and when investigators arrive at the gate location.

Answer 1

Yes, you're correct about both.

Until the Arkham encounter phase, it doesn't really matter that there's a gate there. So you can do whatever you like during movement, including exchanging items.

When you arrive at the Arkham encounter phase, each player in a location with a gate will be drawn in if they haven't been through the gate before. So depending on turn order, as you say, either the player who's been through can close/seal the gate first, or the other player will be drawn in.