Please go back to AF447 Interim Report #1 section 1.6.9.2 to get an explanation on how ACARS messages are managed and time-stamped.
https://www.bea.aero/fileadmin/docum...cp090601e1.pdf
Sorry, the link is for the French version as I cannot find the English one from the BEA website
You can work it out with Google Translate
