Evidence
Talaria Letters 1 & 2

Warning This Section Does Contain Spoilers

The Talaria 1 letter has an air of finality to it that none of the previous letter had. It tells us that we are instructed that this is our final delivery and that we are to start to compile our histories. That we are to be held in our highest esteem. By calling John William James the martyr, it sets his death in concrete. 

The Talaria 2 letter is business as normal and is the same as our very first letter from episode one:

You have received this package from Talaria.

The contents of this package have remained absolutely secret and secure under our protection, per our prerogatives.

Both you and the sender of this package remain anonymous, per our prerogatives.

No address information has been saved, per our prerogatives.