Perfect. That version keeps timestamps
I also tried the GUI, it does not keep timestamp. (winscp)
I also tried with SFTP v3, and I get 1899 as the timestamp. (winscp2)
I ve been trying to get winscp to preserve timestamp for a while now but I still can't do it.
Tried going with a different protocol version, etc...
The weird thing is that winscp is able to know the good timestamp:
. 2017-07-12 11:57:37.019 File: '/AZERTYUI/%BMOCOM-SEND%AZERTYUI-BAIRPTING-MBAIFLE-W%SFTP%ACCEPTED%0efefb00bkrarovp0021glov' [2017-07-12T12:02:32.000Z] 
but when it goes to preserve it:
. 2017-07-12 11:57:37.159 Preserving timestamp [1899-12-30T05:00:00.000Z]
Any chances you could take a look at the log and let me know what I am missing?