P&O have posted the following to their sailing updates page:
“Larne and Cairnryan sailings are currently operating with delays of up to at least x 2 hours. Due to adverse forecast weather conditions we anticipate further disruptions through out the day and would advise ALL passengers with non-urgent travel to ring our Contact Centre to re-arrange. We will not be accepting any new bookings on any sailing from either Larne or Cairnryan at any time today.”