I suppose it must be a bug because the timestamp which I get from the FTP object corresponds exactly with the last modified date of the file (the date which I can see when checking this file on my windows PC)!!!
This date is also returned as TimeStamp from the FTP object. This is exactly what I expect! But, after copying this file (e.g. via ES FileExplorer) OR uploading via FTP object I get always the date of today when calling:
File.LastModified(File.DirDefaultExternal & "/" & "project.txt")
It is obviously not a failure of the FTP object!!