Q: What does the status 'With Editor / Seeking Expert Advice' mean?

Thank you for your question. Indeed, the "Seeking Expert Advice" status is uncommon and is not listed by Elsevier itself in the description of the submission process. Typically, the status "With Editor" is displayed while the manuscript is with the Editor-in-chief or Associate editor before it goes for peer review. If your manuscript status changed to "Seeking Expert Advice" after the "With Editor" stage, it is likely that the Associate editor is in the process of selecting suitable peer reviewers or the manuscript is under peer review, i.e., the status is likely to be in line with the typical "Under Review" status.