The third P&O ship which usually runs from Dover is being inspected today for safety.
The Pride of Canterbury hasn't moved from the port since March 17, when the firm sacked nearly 800 seafarers with no prior warning.
The shock move sparked outrage, with protests taking place across the country, including in Dover, and with calls made to boycott P&O.
The firm said the move was necessary to keep the business afloat, and hired cheaper agency workers to run its ships.
But inspections were needed on the vessels before they could start moving again.
The Pride of Canterbury has yet to be inspected by the Maritime and Coastguard Agency (MCA).
Its Dover-based sister ships, Pride of Kent and Spirit of Britain, have both now passed inspections and services for passengers and freight have resumed on both.
A spokesman for the MCA said today: "A team of surveyors is currently carrying out an inspection of Pride of Canterbury at the request of P&O Ferries.”
All together, 10 P&O ferries will be inspected through the Port State Control regime by the MCA.
Pride of Hull, which runs the Hull to Rotterdam route, Norbay, which runs Liverpool to Dublin, and Norbank, Pride of Rotterdam, European Causeway, and European Highlander, which all sail the Cairnryan – Larne route, have been inspected and cleared to sail, along with the two Dover based ships.
Pride of Kent has had four inspections altogether, three of which were reinspections.
One other ferry is yet to have its full Port State Control inspection.