Where can cargo shuttles land, unload, and load cargo? (Little Upsilon)

Once I purchase my cargo shuttles will I be able to...

1: land at a functioning space center in another player's country? If so, is there a permission-to-land protocol involved?
2: unload my cargo to the other player's space center stock? Again, is there some type of protocol involved?
3: load the other player's cargo, and then transport it to one of my countries or elsewhere?

1. No - the only space centres you can currently use are your own. The second question is therefore not applicable.

2. No and no.

3. No and no.

It is quite possible that some or all of these features will be available at a future date.

Dang it! But many thanks for the info.