How to convert document to pdf/A-1** from command line using --export-to option of soffice.exe programm?

I need to use comand line --convert-to option of soffice.exe for getting pdf/A-1** type of pdf-document.
It is simple possible from window of LibreOffice, but I can’t find an --convert-to option for command line procedure.
Is it possible or not?

Thank you in advance,
Denis

Shamelesly copied from this Quesiton

You seem to have 2 Options

  1. Set the desired option in the UI and afterward the headless output should produce the desired output type.
  2. Use unocnv (GitHub - unoconv/unoconv: Universal Office Converter - Convert between any document format supported by LibreOffice/OpenOffice.) to convert after the fact. (ie. unoconv -f pdf -eSelectPdfVersion=1 your-file.odt )

Hope that (still works) and helps.

Dear Igorlius,
Thank you for your answer, but pdf/A-1 is not a paper size, but is an ISO-standardized version of the Portable Document Format (PDF) specialized for use in the archiving and long-term preservation of electronic documents.
At the same time, PDF/A-1 specifies two levels of conformance PDF/A-1b and PDF/A-1a

We can do it easy by option File > Export to PDF > choose PDF/A-1**
But I do not understand how to make it from command line using --export-to option of soffice.exe programm

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