Sadly, that's beyond my control or influence; though I might mention it to the guy that feeds the files into it. Many thanks for your help.
Before posting, please read how to report bug or request support effectively.
Bug reports without an attached log file are usually useless.
CLNTcommand to all servers that announce a support for the command.
> 2017-02-09 16:34:18.738 FEAT
< 2017-02-09 16:34:19.159 211-Extension supported
< 2017-02-09 16:34:19.752 CLNT
CLNTcommand. Versions of WinSCP prior to the 5.8.1 would probably not send the
CLNTcommand to the server. Can you try an older version of WinSCP? (not that I recommend you using them, it's just to testing purposes)