Sooner or later... Anything that size that can operate underwater will be ready for interplanetary and interstellar space as well, with the right propulsion systems. There is an awful lot of real estate within 50 light years of us that appears to be just like Terra, as per the James Webb telescope's latest findings. The only way this world's entire history, compiled cultural legacies from everybody, and the story of humanity can survive indefinitely through eons is if we branch out and have Terran civilizations on nearby star systems and beyond.
