That refers to any subtle level which is related to this one, and any from which one can be reached mentally or emotionally by someone who is involved in this one.

For instance, if you are in rural Estonia, you may not have a cell phone. Thus, even though nearly everyone in the UK has such a phone, none of those persons can reach you. But if you have a phone there and it has a satellite connection, you can be reached.

But we can assume that if you are in the USA, then there are several ways people from the UK can reach you. It might be possible that you could be extradited. 

In some meditation experiences, one may find that if one goes to a deep level, one loses contact with this physical world and its psychic communication. But as soon as one resumes the physical body here, contacts here mentally assault one and one must always act physically to satisfy demands pertaining to this place.

In some deep meditations, one may see an energy coming from someone who is physically involved. One may dodge that energy by going to another plane of existence in the astral realm. That would put one out of reach for the time being.