Celebrity Cruises announced a delay in embarkation for passengers scheduled to board the Celebrity Apex on May 25 in Southampton, after the ship reported gastrointestinal outbreak during the previous voyage.

The cruise line confirmed that several passengers on the 8-night roundtrip cruise departing May 17 reported symptoms of acute Gastrointestinal illness.

“Out of an abundance of caution, we’ve heightened our enhanced sanitizing protocols before you board, both within the terminal and onboard the ship,” the message said. As part of this protocol, embarkation will now begin at 1:30 p.m., two hours later than scheduled. All guests must be onboard by 4:30 p.m., with final check-in by 3:30 p.m. Celebrity is also urging guests not to arrive before their assigned boarding times to prevent terminal congestion.

Despite the deep-cleaning delay, the upcoming 11-night voyage is set to sail as scheduled, calling on Copenhagen, Stockholm, Helsinki, Tallinn, and Visby.

Celebrity Cruises said that the health and safety of guests remains their top priority as they continue to monitor the situation closely.