In the 1990s, the service has been gradually harmonised with the closing of several existing gaps in the hourly schedule in the morning and provided additional services during the peak hour.
Originally it was planned that from December 2012, after of the reorganisation and expansion of the Rostock S-Bahn, the new S4 line would operate from Rostock Seehafen Nord via Rostock Hbf to Warnemünde.