Think this partly related to the issue I was seeing here : https://www.flashfxp.com/forum/flash...-question.html
To me, it looks like there is some conflict/resolution issue relating to Time tracking preferences in FlashFXP, and Preserve File date settings.
To me ... MDTM / Preserve File date should bypass any Time setting UTC conversion preferences?
One FTP I use, I see some files once downloaded being correct ... and others being out by one hour as well. Think this is related to how a file listing from the FTP, some files come in with just a date, but without a timestamp and some other files have the date and time settings come through ok. MDTM is able to retrieve the correct date and time ... but something in the process is trying to convert the time... instead of preserving the date/time retrieved.