[...]
[Following the guidance of the 'Disciple Holy Land Seat Certificate', you arrive at the 11th Council Hall…]
[The host's platform and many seats within the council hall are empty, clearly, it's not time for the meeting yet.]
[Alone, you step in front of the host's platform where a stack of blank notes is placed.]
[Do you want to leave a message on the note?]
Leaving a note is a way to bypass the 'Book of Letters'. You don't need to know the other party's soul imprint, knowing their alias in the New World is enough to send them a private message.
Amos, being the eleventh disciple, could send private messages to all the apostles under him from the 11th council hall. Except for the sender and receiver of the private message, nobody else could see the message on the note.
However, Lin Xun suspected that as long as he left a message here, Amos would definitely know its content.