Buenos Aires

A few days ago the pope’s letter and the Argentine directives to which he was replying appeared on the Vatican’s website (Spanish, English), setting off a fresh tizzy of concerns about the level of authority to be accorded them in light of their now being posted at vatican.va.
Canonist Dr Ed Peters tries to make some sense of this here. He states:

Buenos Aires directives themselves, amid their copious platitudes and euphemisms, manage to avoid, if perhaps more narrowly than does Amoris, directly answering the key question raised by Amoris in this area. Thus, the near-universal conclusion, applauded by some and deplored by others, that the pope in Amoris, or at the very least in his endorsement of the Buenos Aires document, has indeed established that, ‘Yes, divorced-and-remarried Catholics, while living sexually active lives, may licitly approach for and be administered holy Communion’—as, I grant, the Maltese bishops plainly say and as the German episcopal committee effectively holds—is a source of consternation. Oh well.

...in my professional opinion, the three levels of canonical authority to be ascribed to Church documents in virtue of their being published on the Vatican’s website: None, Zero, or Zip.

It's clear from Ed's comments that the appearance of a papal document on the Vatican website does not carry any special canonical consequences.

Irrespective of the juridical position, the official publishing would seem to constitute a ramping up of rhetoric to reinforce the pope's position on this issue and suggests that there is no backing down for him!

There is a more nuanced examination of the meaning of this from Sandro Magister here, entitled No End to the Tempest of "Amoris Laetitia." Francis doesn't like things quiet which, ultimately boils down to this:

In short, there remains the original sin of the confused and botched composition of “Amoris Laetitia,” and especially of its eighth chapter. But evidently that’s the way Francis likes it.