Simultaneous Reference is when the person acts as the astral body but while acting is aware that the astral body does not have the physical body access but the self can also reach and use that physical access even though the subtle body does not have a direct connection to it.

Expanded explanation

The self can also reach and use that physical access even though the subtle body does not have a direct connection to it. This can happen because even though the subtle body is displaced or separated from the subtle one, the coreSelf’s desires for physical action may be serviced by the kundalini which is in the physical body. A transmission of the desire of the core may be sensed or absorbed by the kundalini, which will respond to that as if it is an instruction to act or not to act.

Regarding the meaning of self/coreSelf:

Self means coreSelf except when it is used to main the composite self or normal meaning of self in English. Mostly in my literature, self means coreSelf.