--convert-to option exits immediately

When I try to use the --convert-to option on the command line to convert a document to a new format, LibreOffice exits immediately with exit code 0. Here an example:

me@localhost:~> libreoffice --convert-to xls $MY_ODS ; echo $?
0

This happens regardless of the source and target formats. I have used this option a lot in the past to do bulk conversions in headless mode and am unsure as to why it’s no longer working. Any suggestions?

RFO