The version in Debian buster will probably not change, but LibreOffice maintainers for Debian have been uploading new versions of LibreOffice to backports.debian.org. The current version in backports is 6.4.5. Debian unstable has 7.0.0-rc2, so it will likely be updated to 7.0.0 soon, followed shortly by an update to backports.
Thanks for this, have added the links to my blog post, but will check this out, for some reason LO6.4.x makes a mangle of a docx file, I think docx must save content from earlier documents which LO is finding.
I blame MS office not LibreOffice for this.
Out of interest can I e-mail said file to someone, it may help the developers know what they are up against with saved docx files.