Water levels go up and down.... ground elevation goes up and down. It might be significant or not. It might relate to something natural or not. It might have been the result of things such as tectonic plates shifting or not. Hard to get too excited about much of this except in an “well that’s interesting...” sort of way.
“The ancient city of Ephesus was an important port city and commercial hub from the Bronze Age to the Minoan Warm period, and continuing through the Roman Empire. An historic map shows its location right on the sea. But today, in modern-day Turkey, Ephesus is 5 km from the Mediterranean. Some historians erroneously claim “river silting” caused the change, but the real “culprit” was sea level change.”
Source: WUWT (not exactly the BBC but yeah)
https://wattsupwiththat.com/2013/12/02/history-falsifies-climate-alarmist-sea-level-claims/