Moving this discussion to the InDesign forum.
What Os and version?
Do you really need distilling?
Nowadays directly exporting PDF files is the recommended method of creating PDF files, isn't it?
Consider creating new document of A3 size, placing (File>Place) your original A4 indd doc here, resizing to fit and exporting pdf.
Direct resizing not always works smoothly, so placing is preferable.
It takes longer to write the procedure down than to do it
File > Print > Printer dropdown > Postscript File
Postscript workflows are not recommended.